 Complete the following phrase:  In 1940, after securing the assent of Nazi Germany through the MolotovRibbentrop Pact, the Soviet Union pressured Romania, under threat of war, into withdrawing from Bessarabia, allowing the Red Army 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 inhabited by Slavic majorities 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 