The prewar eastern Polish territories of Kresy, which the Red Army had overrun during the Nazi-Soviet invasion of Poland in 1939 (excluding the Białystok region) were permanently annexed by the USSR, and most of their Polish inhabitants expelled. As a result of the Potsdam agreement to which Poland's government-in-exile was not invited, Poland lost 179,000 square kilometres (69,000 square miles) (45%) of prewar territories in the east, including over 12 million citizens of whom 4,3 million were ethnically the speakers of Polish. Today, these territories are part of sovereign Belarus, Ukraine, and Lithuania.[9]