Introduction
While there have been many studies on the lawfulness and effectiveness of multilateral sanctions in comparison with unilateral sanctions, there has been little discussion of how a sanctions alliance is organized and why members of the alliance join the sanctioning campaign. The sanctioning nations appear to join the drive voluntarily because they all have the same objectives and incentives, but this is not always the case.
After US President Barack Obama signed the Comprehensive Iran Sanctions, Accountability, and Divestment Act of 2010 (CISADA) on July 1, 2010,Footnote 1 which requires that sanctions be imposed on companies engaged with Iran’s energy sector, US allies such as the EU, Canada, Australia, and Japan followed suit, announcing their own independent sanctions against Iran. South Korea was dismayed by US pressure to join the US-led drive in the face of Iran’s warnings of economic retaliation. Unlike the US, South Korea had maintained friendly diplomatic relations with Iran. Also, South Korea and Iran were important to each other as trading partners. In other words, while the US is and has long been South Korea’s most important ally in every respect, with South Korean exports of over $100 billion of goods to the US in 2022,Footnote 2 South Korea was unable to ignore the importance of Iran, given the overall impact of the Iranian sanctions on the Korean economy as well as diplomatic backlash from Tehran.
While the US had maintained sanctions against Iran since 1979, international sanctions against Iran were tightened considerably from September 2010 through January 2016, when the JCPOA was implemented. During and since that time, the Korean government walked a tightrope between the US and Iran. On the one hand, South Korea participated in the US imposition of sanctions on Iran by imposing measures substantially identical to those imposed by the US. On the other hand, while Seoul implemented its own independent sanctions against Iran from time to time, South Korea also maintained its diplomatic and commercial relationship with Iran.
In this chapter, I shall explore how South Korea found itself walking a tightrope, beginning in 2010. It then becomes clear why South Korea hesitated when introducing autonomous Iranian sanctions; how Washington pressured Seoul to join the US-led Iranian sanctions; how the US and its sanctions directly affected and changed the Korean sanctions regime against Iran from time to time; and, in the end, how South Korea organized its unique sanctions regime. Finally, I conclude this chapter by revisiting the commonly held views of multilateral sanctions, and what drives such alliances.
Two Old Friends: Tehran and Seoul
Unlike the relationship between the US and Iran, Iran and South Korea had steadily strengthened their ties since establishing diplomatic relations in 1967.Footnote 3 When Korean people talk about friendly relations between the two countries, they invariably mention Teheranno, also known as “Tehran Street,”Footnote 4 in Seoul. The 3.7-kilometer-long ten-lane Tehran Street, running through Seoul’s affluent Gangnam district from east to west, is the only main road in Seoul that has a foreign name. In 1977, the Mayor of Tehran proposed to his counterpart, the Mayor of Seoul, that they exchange names for streets in their capital cities. In response to Tehran Street, the Mayor of Tehran named the 3-kilometer-long road, which runs in the north part of the capital and has four to six lanes, Seoul Boulevard. This prominent symbolism speaks volumes about the positive relationship between Iran and South Korea.Footnote 5
The economic relationship between the two states is what connects them the most. South Korea’s total export value to Iran reached $3.1 billion in 2009, making it the fifth largest exporter to Iran in the world. South Korea imported 81.4 million barrels of oil from Iran in 2009, representing 9.6 percent of the total volume of oil imported by South Korea.Footnote 6 Further, the growth in the usage of Korean engineering and construction firms in Iranian construction continued.Footnote 7 From 1975 to 2010, the value of orders that South Korean engineering and construction firms received from Iranian entities amounted to $119 billion. Iran ranked sixth among all the countries in which Korean engineering and construction companies operated.Footnote 8
Before the Sanctions: Seoul’s Hot Summer in 2010
Let’s wind back the clock to Seoul in August of 2010. After enacting CISADA, Washington began to put pressure on its allies, including South Korea. Obama regularly and personally checked on Seoul’s “strategic choice,” and Robert Einhorn, US special adviser for nonproliferation and arms control, visited Seoul, to push South Korea to join the US sanctions against Iran.Footnote 9 Meanwhile, through multiple channels, Iran warned that it would retaliate if South Korea acquiesced in the US demand to go beyond the sanctions regime under the resolutions of the UNSC. For instance, a senior Iranian lawmaker, Parviz Sorour, said “We warn other states, [e]specially South Korea, not to tie their national interests with those of the Americans. They should know that Iran will take punitive measures if it comes under sanctions.”Footnote 10
The Korean government was thus caught in a difficult dilemma. On the one hand, it had no choice but to join the US sanctions on Iran given that the US was its strongest ally. On the other hand, Seoul was afraid of losing an important energy source and one of its biggest export markets in the Middle East. In Seoul, public opinion was not only extremely divided, but opinion was divided even among different departments of the Korean government. The Foreign Ministry, prioritizing the US–South Korea alliance, encouraged the introduction of autonomous Korean sanctions against Iran. They were sharply opposed by the Ministry of Strategy and Finance, which was more concerned with economic ties with Iran and potential retaliation by Tehran.Footnote 11 Even within the Foreign Ministry, there were sharp conflicts between two groups, a pro-US group prioritizing the Washington–Seoul alliance and a pro-Middle East group emphasizing regional sentiments.Footnote 12 This diversity of opinions directly reflected the Korean government’s deep internal conflict.
The Start of the Sanctions: Walking a Tightrope between the US and Iran
Seoul’s hot summer of 2010 passed into fall, and South Korea released the “Announcement by the Korean Government regarding Implementation of the United Nations Security Council Resolution 1929” (the “Announcement”) of its sanctions against Iran,Footnote 13 in the four sectors of finance, international trade, transportation and travel, and energy.Footnote 14
But it was just the beginning of Korean-style tightrope walking. Its reluctance to join the sanctions seemed evident. First, South Korea was the last of the US allies to join the US-led Iranian sanctions.Footnote 15 Second, the Korean government did not invoke any US sanctions, including CISADA, as the basis for its own measures. It invoked instead the UNSC resolutions, including Resolution 1929,Footnote 16 even though virtually every Korean sanction measure was identical to a measure in CISADA. Last, the Korean government introduced Korean won-based settlement accounts for normal and lawful transactions with Iranian parties in Korean banks, under the name of the CBI.
Unfortunately, the Obama administration continually pressed for further Korean sanctions against Iran. Robert Einhorn visited Seoul on December 5, 2011 to call for South Korea’s cooperation with the US sanctions, in particular, prohibiting purchases of Iranian petrochemical products.Footnote 17 Following Washington’s pressure, on December 16, 2011, the Korean government released the second announcement (1) requiring Korean companies to pay attention to transactions in connection with purchasing Iranian petrochemical products;Footnote 18 and (2) blacklisting 99 Iranian entities and six individuals.Footnote 19
After Obama signed the 2012 National Defense Authorization Act (NDAA 2012),Footnote 20 Einhorn urged South Korea to reduce purchases of Iranian crude oil and unwind financial dealings with the CBI.Footnote 21 In response to the US pressure, Iran warned that it would retaliate by suspending all South Korean imports,Footnote 22 and would reconsider the ties between the two countries.Footnote 23 South Korea finally agreed to slash its oil imports from Iran by at least 18 percent every 180 days.Footnote 24 This led to Washington granting South Korea a waiver of sanctions under NDAA 2012 on June 11, 2012,Footnote 25 which enabled South Korea to import Iranian crude oil with continuous reductions.Footnote 26
In the meantime, diplomatic efforts by Seoul continued in an attempt to appease Tehran’s anger, especially due to Korea’s reduction of Iranian oil purchases. After Iran threatened retaliation in response to Korea’s participation in sanctions under NDAA 2012, several Korean officials visited Iran in July 2012 to explain Korea’s troubling position between the US and Iran.Footnote 27 After Iranian President Hassan Rouhani’s election, a group of senior officials from both parties’ foreign ministries discussed how to bolster bilateral ties in October 2013.Footnote 28 One month later, a high-level policy consultation was held between the Korea’s Deputy Foreign Minister for Political Affairs and Iran’s Deputy Foreign Minister for Asia-Pacific Affairs to discuss ways to bolster bilateral ties.Footnote 29
The Implementation of the Sanctions: An Unprecedented Sanctions Regime
Under the Korean sanctions regime against Iran, sanctions on trade and finance played a pivotal role. Importantly, Korean private institutions were the entities that primarily implemented the sanctions measures on trade and investment. Meanwhile, South Korea implemented its financial sanctions against Iran through pre-existing and new regulatory frameworks,Footnote 30 as well as governmental bodies and two state-owned banks.
Korean Sanctions on the Trade and Investment Sector
On the date of the Announcement, South Korea’s Iran Trade and Investment Guidelines,Footnote 31 an exact copy of CISADA, were announced by a private institution, the KITA.Footnote 32 Among other things, all Korean individuals and business entities must not engage in certain “Prohibited Activities”:Footnote 33 (1) export of significant goods or services (equivalent to making an investment) materially and directly facilitating Iran’s development of petroleum resources in Iran; (2) export of significant goods or services materially and directly facilitating Iran’s production of refined petroleum products; (3) export of significant goods or services materially and directly facilitating Iran’s import of refined petroleum products; and (4) export of refined petroleum products to Iran,Footnote 34 under the Iran Trade and Investment Guidelines.Footnote 35
According to the Iran Trade and Investment Guidelines, any Korean individuals and entities intending to trade with Iranian parties or invest in Iran in a way that does not fall within the category of the Prohibited Activities must complete a confirmation form for Unprohibited Trade and Investment (the “Confirmation Form”) and apply to the Korea Strategic Trade Institute (KOSTI),Footnote 36 a government-affiliated institute, for approval of the confirmation. The KOSTI then examines, within fifteen days, whether the applicant’s Iranian counterpart, items, and activities comply with the Iran Trade and Investment Guidelines.Footnote 37 After the KOSTI validates the Confirmation Form, the applicant submits the Confirmation Form to the financial institutions,Footnote 38 enabling the applicant to access financial services.
Korean Sanctions on the Finance Sector
The day after the Announcement, the Ministry of Strategy and Finance amended the Notification on the Approval of Payments and Receipts for Implementation of Maintaining International Peace and Security (the “Notification on the Approval of Payments and Receipts”),Footnote 39 adding 102 entities and twenty-four individuals to the list of “Financially Restricted Persons.” As a result, any payment or receipt of money to or from those entities and individuals was barred without prior approval of the Bank of Korea.
Four months later, the Ministry of Strategy and Finance issued a notification, identical to the EU sanctions measure,Footnote 40 requiring, from the Bank of Korea, (1) prior approval for all financial transactions of €40,000 or more (or a series of transactions where each transaction is €10,000 or more and the aggregate amount is €40,000 or more in any given twelve-month period); and (2) a prior report for all financial transactions of €10,000 or more involving Iranian parties that were not in the above list of Financially Restricted Persons.Footnote 41
Once an application was submitted, the Bank of Korea screened it, within ten to fifteen days, to determine whether the items and activities involved in the underlying transaction were Prohibited Items or Prohibited Activities of the Iran Trade and Investment Guidelines by the KITA. It then issued the approval or the report to the applicant if there was nothing wrong.Footnote 42
Thus, the Korean government structured the framework of its sanctions regime as follows: If a Korean individual or entity made a trade with an Iranian party (1) in the Prohibited Items or Prohibited Activities; and/or (2) without the prior approval or notification from the Bank of Korea, the transaction would violate the Korean Foreign Exchange Act eventually. These unprecedented levels of bureaucratic requirements reflected the tension between the US pressure to suspend all trades with Iran and the Korean government’s will to protect trade with Iran at all costs.
Korean Won-Based Settlement System
On September 17, 2010, to facilitate financial transactions between Korea and Iran, the Korean government established a complex system for won-based settlement accounts, reflecting the government’s commitment to continued trade with Iran, even as Korea imposed sanctions in alliance with the US. Korean won-based settlement accounts were opened under the name of the CBI in two Korean state-owned commercial banks, Woori Bank and Industrial Bank of Korea (IBK). This made possible legitimate financial transactions with Iran by transferring money between the two states without any physical money actually moving (see Figure 17.1).Footnote 43

Figure 17.1 Payment structure of Korean won-based settlement.
Under this arrangement, the CBI opens Korean won-based settlement accounts in Woori Bank and IBK, receives oil payments from Korean refineries in Korean won, and reserves the payments in its accounts in the two banks. Later, when Iranian importers try to purchase Korean goods, the importers’ Iranian banks establish letters of credit and notify Korean exporters of the issuance of the letter of credit through the CBI and Woori Bank or IBK. After the Korean exporters ship the goods to Iran, they, by submitting shipping documents, including bills of lading to Woori Bank or IBK, receive payments in Korean won from the account of Iran’s Central Bank in Woori Bank or IBK (see Figure 17.2).Footnote 44

Figure 17.2 Process of payment and receipt for Iranian parties.
The Korean won-based settlement accounts, an idea of Seoul’s officials,Footnote 45 has played a pivotal role in bridging bilateral economic relations. It is a precious link with the outside banking world from Tehran’s perspective, in part because many of Iran’s banks were expelled from SWIFT, the global financial messaging hub that is critical for bank-to-bank transactions. In addition, the Korean won-denominated system was one of only a few banking channels connecting Iran with the US’ allies.Footnote 46 It was also the only (unofficially) US-approved banking network with Iran for quite a long time.
The Guideline on Payment and Settlement,Footnote 47 together with the announcement of the Iran Trade and Investment Guidelines, were published by the Korea Federation of Banks (KFB).Footnote 48 Korean banks must follow the Iran Trade and Investment Guidelines and the Notification on the Approval of Payments and Receipts. For example, before Korean banks facilitated a financial transaction relating to any Iranian parties, banks required the Confirmation Form under the Iran Trade and Investment Guidelines.
An Analysis
We have examined how the Korean government implemented sanctions against Iran through a unique mix of mechanisms: (1) guidelines issued by private institutions that are substantially identical with the US sanctions, that is to say, Iran Trade and Investment Guidelines; (2) implementation by government-affiliated institutes, for example, KOSTI’s Confirmation Form; (3) pre-existing regulatory frameworks, for example, the Notification on the Approval of Payments and Receipts; and (4) new regulatory frameworks, for example, the Bank of Korea’s approval and report requirement. We have also seen that this government-led mechanism arose from Seoul’s strong political, diplomatic, and economic concern to avoid Tehran’s retaliation.
Seoul’s approach to Tehran during the sanctions era was largely successful. On the one hand, the Korean government’s participation in the US drive delivered a very clear message to Iran that US allies strongly and firmly backed the US Iranian policy regardless of their national interests. On the other hand, by maintaining bilateral trade, South Korea has never been subjected to any countermeasures from Iran. While bilateral trade between Iran and South Korea has fluctuated greatly, depending on the sanctions, the trade volume between Iran and South Korea continues to be substantial. Trade reached its peak in 2011 ($17.426 billion) thanks to the introduction of the Korean won-based settlement accounts; plummeted sharply during 2012–2015, recording $6.098 billion in 2015, due to the reinforced Iranian sanctions, inter alia, strengthened financial sanctions by NDAA 2012; and showed signs of recuperation after Implementation Day of the JCPOA during 2016–2017, recording $12.010 billion in 2017.Footnote 49
The Korean won-denominated accounts were a critical means of maintaining trade with Iran and must be one of the reasons that Iran did not retaliate. Although the payment structure of Korean won-based settlement required both banks and traders to invest significant effort in compliance due to its complicated arrangement, this settlement system made it possible for Iran and South Korea to maintain trade relations in the face of the sanctions. And it was one of the few international banking channels approved by the US, during a period when Iran was rapidly losing access to international banking.
Post-2016
During the Trump presidency, ironically, there was no apparent dilemma by South Korea since that administration made it virtually impossible for South Korea and Iran to have any meaningful diplomatic and economic relations. At the outset, the Trump administration approved waivers for South Korea to continue importing oil from Iran. But before long, the White House announced an end to the exemptions, and Woori Bank, IBK, and the CBI stopped all won-denominated settlement services on May 2, 2019, in line with the expiration of waivers on that day.Footnote 50 As a result, the trade volume between South Korea and Iran dropped from $2.416 billion in 2019 to $195 million in 2020.Footnote 51 Also, because South Korea froze some $7 billion of Iran’s assets being held by Woori Bank and IBK under pressure from the Trump administration, in apparent retaliation, Iran seized a Korean vessel in January 2021, pressuring South Korea to release the funds. South Korea proposed to use part of the funds for paying Iran’s UN contributions or Covid-19 vaccines by using the SHTA, with the cooperation of the Biden administration, and Iran eventually released the ship.Footnote 52
Conclusion
By structuring a unique sanctions regime and operating a Korean won-based banking channel, South Korea successfully walked a tightrope between the pressure from the US, its major economic and political ally, and the pressure from Iran, with which it had a singular and longstanding friendship. South Korea accomplished this delicate maneuver through creating a complicated system that could not easily be replicated by other nations.
At the same time, this Korean case reveals a dimension of the sanctions alliance that is not often addressed: Not all countries participating in a sanctions alliance are pleased about doing so. Amid deep concerns regarding expected disadvantages, South Korea chose to be a member of the Iran sanctions alliance in response to US pressure. Indeed, this is a good example showing that each sanctioning nation may in fact be ambivalent, or deeply reluctant, and is participating not out of a shared commitment to the sanctioning campaign, but rather in response to continued pressure from a powerful ally they cannot afford to alienate.

