Until 1940 they were openly hostile, in 1948 they deteriorated again and in 1949 were completely broken. In 1953–1955 period, bilateral relations were restored with the signing of Belgrade declaration, but until the collapse of Yugoslavia they remained very restrained. Relations with Soviet Union were of high priority for Belgrade as those relations or their absence helped the country to develop the principle of Cold War equal-distance on which the Yugoslav non-alignment policy was based.[1]