Since August 2014, a monitoring survey at a frequency of 111 MHz has been conducted on the Large Phased Array (LPA) radio telescope of the P.N. Lebedev Physical Institute (LPI). We report the discovery of a bright pulse having a dispersion measure (DM) equal to
$134.4\pm2\ \text{pc cm}^{-3}$, a peak flux density (
$S_p$) equal to
$20\pm4$ Jy, and a half-width (
$W_e$) equal to
$211\pm6$ ms. The excessive DM of the pulse, after taking into account the Milky Way contribution, is
$114\ \text{pc cm}^{-3}$ that indicates its extragalactic origin. Such value of DM corresponds to the luminosity distance 713 Mpc. The above parameters make the pulse to be a reliable candidate to the fast radio burst (FRB) event, and then it is the second FRB detected at such a large
$\lambda\sim2.7$ m wavelength and the first one among non-repeating FRBs. The normalised luminosity
$L_\nu$ of the event, which we have designated as FRB 20190203, estimated under assumption that the whole excessive DM is determined by the intergalactic environment towards the host galaxy, is equal to
$\simeq 10^{34}\ \text{erg s}^{-1} \text{Hz}^{-1}$. In addition to the study of radio data we analysed data from the quasi-simultaneous observations of the sky in the high energy (
$\geq 80$ keV) band by the omnidirectional detector SPI/ACS aboard the INTEGRAL orbital observatory (in order to look for a possible gamma-ray counterpart of FRB 20190203). We did not detect any transient events exceeding the background at a statistically significant level. In the INTEGRAL archive, the FRB 20190203 localisation region has been observed many times with a total exposure of
$\sim 73.2$ days. We have analysed the data but were unable to find any reliable short gamma-ray bursts from the FRB 20190203 position. Finally, we note that the observed properties of FRB 20190203 can be reproduced well in the framework of a maser synchrotron model operating in the far reverse shock (at a distance of
$\sim 10^{15}$ cm) of a magnetar. However, triggering the burst requires a high conversion efficiency (at the level of 1%) of the shock wave energy into the radio emission.