In 1940, after securing the assent of Nazi Germany through the Molotov–Ribbentrop Pact, the Soviet Union pressured Romania, under threat of war, into withdrawing from Bessarabia, allowing the Red Army to enter and the Soviet Union to annex the region. The area was formally integrated into the Soviet Union: the core joined parts of the Moldavian ASSR to form the Moldavian SSR, while territories in the north and the south of Bessarabia were transferred to the Ukrainian SSR. Axis-aligned Romania recaptured the region in 1941 with the success of Operation München during the Nazi invasion of the Soviet Union, but lost it in 1944 as the tide of war turned. In 1947, the Soviet-Romanian border along the Prut was internationally recognised by the Paris Treaty that ended WW2.
During the process of the dissolution of the Soviet Union, the Moldavian and Ukrainian SSRs proclaimed their independence in 1991, becoming the modern states of Moldova and Ukraine while preserving the existing partition of Bessarabia. Following a short war in the early 1990s, the Pridnestrovian Moldavian Republic was proclaimed in the Transnistria, extending its authority also over the municipality of Bender on the right bank of Dniester river. Part of the Gagauz-inhabited areas in southern Bessarabia was organised in 1994 as an autonomous region within Moldova.
