Prime Minister William Lyon Mackenzie King, working closely with his Foreign Minister Louis St. Laurent, handled foreign relations 1945–48 in cautious fashion. Canada donated money to the United Kingdom to help it rebuild; was elected to the UN Security Council; and helped design NATO. However, Mackenzie King rejected free trade with the United States, and decided not to play a role in the Berlin airlift. Canada had been actively involved in the League of Nations, primarily because it could act separately from Britain. It played a modest role in the postwar formation of the United Nations, as well as the International Monetary Fund. It played a somewhat larger role in 1947 in designing the General Agreement on Tariffs and Trade.