In the Southeastern part of occupied Polish territories, there have been long-standing tensions between the Polish and Ukrainian populations. Poland's plans to restore its prewar borders were opposed by the Ukrainians, and some Ukrainian groups' collaboration with Nazi Germany had discredited their partisans as potential Polish allies. While the Polish government-in-exile considered tentative plans about providing a limited autonomy for Ukrainians, in 1942 the staff of the Home Army of Lviv recommended deporting 1–1.5 million Ukrainians to the Soviet Union and settling the remainder in other parts of Poland once the war ended. The situation escalated the next year when the Ukrainian Insurgent Army (Українська повстанська армія, "Ukrayins'ka Povstans'ka Armiya", UPA), a Ukrainian nationalist force and the military arm of the Organization of Ukrainian Nationalists (Організація Українських Націоналістів, "Orhanizatsiya Ukrayins'kykh Natsionalistiv", OUN), directed most of its attacks against Poles and Jews. Stepan Bandera, one of UPA's leaders, and his followers concluded that the war would end in the exhaustion of both Germany and the Soviet Union, leaving only the Poles—who laid claim to East Galicia (viewed by the Ukrainians as Western Ukraine, and by the Poles as Eastern Poland)—as a significant force, and therefore the Poles had to be weakened before the war's end.