Policies on the demand side of fossil fuels are not enough to fight against climate change, and policies on the supply side should be adopted as supplements. The idea of phasing out fossil fuels at the starting point of the energy chain, despite the fact that it has not yet been legally binding, has been seriously discussed in the Conference of the Parties. In this regard, the special situation of highly fossil fuel-dependent countries (HFFDCs), such as Iraq and Azerbaijan, should be fully considered under Article 4.8 of the United Nations Framework Convention on Climate Change. This article seeks to analyse the legal approach and arguments of the HFFDCs and the non-fossil fuel-dependent countries (NFFDCs), such as Austria and Sweden, towards policies and initiatives to phase out fossil fuels. The NFFDCs, relying on the just transition stemming from principle of Common but Differentiated Responsibilities and Respective Capabilities, have put forward the initiatives of creating a non-binding coalition and a binding treaty in analogy with the Non-Proliferation of Nuclear Weapons. In contrast, the HFFDCs, based on the principle of permanent sovereignty over natural resources, have presented the Net Avoided Emission and phasing out fossil fuel emissions initiatives. Each party has a fundamental criticism of the legal arguments and the initiative of the other party. The idea of the Office of the High Commissioner for Human Rights in 2018 to promote the human right to equitable development can reconcile the parties’ arguments. This idea requires the NFFDCs to cooperate with the HFFDCs in improving the level of human development and reducing the economic and social effects rising from phasing out fossil fuels in the HFFDCs.