In 1947–1948, the Soviet Union attempted to command obedience from Yugoslavia, primarily on issues of foreign policy, which resulted in the Tito-Stalin split and almost ignited an armed conflict. A period of very cool relations with the Soviet Union followed, during which the US and the UK considered persuading Yugoslavia into the newly formed NATO. This changed in 1953 with the Trieste crisis, a tense dispute between Yugoslavia and the Western Allies over the eventual Yugoslav-Italian border (see Free Territory of Trieste), and with Yugoslav-Soviet reconciliation in 1956.