António de Oliveira Salazar
Despite the authoritarian character of the regime, Portugal did not experience the same levels of international isolation as Spain did following World War II. Unlike Spain, Portugal under Salazar was accepted into the Marshall Plan (1947–1948) in return for the aid it gave to the Allies during the final stages of the war. Furthermore, also unlike Spain, it was one of the 12 founding members of the North Atlantic Treaty Organisation (NATO) in 1949, a reflection of Portugal's role as an ally against communism during the Cold War in spite of its status as the only non-democratic founder. In 1950, Portugal joined the European Payments Union and participated in the founding of the European Free Trade Association (EFTA) in 1960 and the Organisation for Economic Co-operation and Development in 1961. It joined the General Agreement on Tariffs and Trade in 1962, and finally, Portugal signed a free trade agreement with the European Economic Community in 1972, still under the auspices of the "Estado Novo".
Rhodesian mission in Lisbon
British policy-makers regarded Portugal as a traditional friend—the Anglo-Portuguese Alliance dated back to 1386, and both countries were in the North Atlantic Treaty Organisation (NATO) and the European Free Trade Association—but the combined strength of the communist bloc and the Afro-Asian lobby in the United Nations forced the British to peel back their support for the pluricontinental "Estado Novo" ("New State") during the early 1960s. Portugal's Colonial War, starting in Angola in 1961, pitted it against a number of guerrilla factions in its African territories, most of which subscribed to communist political thinking. Britain opposed communist encroachment into southern Africa, but knew it would become an international pariah if it publicly opposed general consensus at the UN, which roundly condemned colonialism in all forms and supported communist-backed insurgencies across the region, regarding them as racial liberation movements. It therefore attempted an awkward balancing act whereby it would appear to oppose Portugal without meaningfully doing so.