 The new border was short-lived as Nazi Germany invaded the Soviet Union.In 1945 following the end of the war and the establishment of the Polish People's Republic a new border was formed between the Ukrainian SSR and Poland with Poland losing vast territories in Ukraine's favor, including the city of Lviv.During the negotiations on the Polish–Soviet border agreement of August 1945, alongside the Polish-Ukrainian section of the border the Polish side proposal was categorically rejected.