 The Soviet Union initially also believed it was possible to include at least Western Thrace in the post-war borders of Bulgaria and thereby to secure a strategic outlet to the Aegean Sea.But the United Kingdom, whose troops advanced towards Greece at the same time, stated that the withdrawal of Bulgarian troops from all occupied territories was a precondition for a ceasefire agreement with Bulgaria.As result on 10 October, the Bulgarian army and administration began evacuating and after two weeks withdrew from the area.