Finland was restored to its borders of 1 January 1941 (thus confirming its territorial losses after the Winter War of 1939-40), except for the former province of Petsamo, which was ceded to the Soviet Union. In Finland, the reparations and the dictated border adjustment were perceived as a major injustice and a betrayal by the Western powers, after the sympathy Finland had received from the West during the Soviet-initiated Winter War. However, this sympathy had been eroded by Finland's collaboration with Nazi Germany between 1941 and 1944. During this time, Finland not only recaptured territory it had lost in 1940, but continued its offensive deeper into Soviet lands, occupying a broad strip of Soviet territory. This prompted the United Kingdom to declare war on Finland in December 1941, further weakening political support in the West for the country. The Soviet Union's accessions of Finnish territory was based on the Moscow Armistice signed in Moscow on 19 September 1944 and resulted in an extension of the accessions in the Moscow Peace Treaty that ended the Winter War.