 On 15 February 1951 the governments of People's Republic of Poland and Soviet Union signed a bill which ratified the change of the eastern border of Poland.According to the agreement, Poland transferred to the Ukrainian Soviet Socialist Republic of territory located west of the town of Sokal, which had been located in the Hrubieszów county of the Lublin Voivodeship (together with the towns of Bełz, Krystynopol and Uhnów as well as the rail line Rawa Ruska - Krystynopol).These towns are now located in the Sokal Raion of the Lviv Oblast.