A military conflict involving British, French, Israeli, and Egyptian forces. It arose from the nationalization of the Suez Canal Company by Egypt in 1956. When attempts to establish an international authority to operate the Canal failed, Britain and France entered into a military agreement with Israel. The latter, concerned at the increasing number of fedayeen or guerrilla raids, was ready to attack Egypt. On 29 October Israel launched a surprise attack into Sinai, and Britain and France issued an ultimatum demanding that both Israel and Egypt should withdraw from the Canal. This was rejected by President Nasser. British and French planes attacked Egyptian bases, and troops were landed at Port Said. Under pressure from the USA, with the collapse of the value of sterling, and mounting criticism of most other nations, the Anglo-French operations were halted and their forces evacuated. A UN peacekeeping force was sent to the area. The US Secretary of State, J. F. Dulles, formulated the short-lived Eisenhower Doctrine (1957), offering US economic and military aid to Middle East governments whose independence was threatened. Israeli forces were withdrawn in March 1957 after agreement to install a UN Emergency Force in Sinai and to open the Straits of Tiran to Israeli shipping.