Egyptian president Gamal Abdel Nasser nationalized the Suez Canal Company on 26 July 1956, placing its assets under Egyptian control and promising compensation. Britain and France opposed the takeover and sought international control; Israel had separate disputes with Egypt over attacks, the Canal restrictions and the Straits of Tiran. In October, Israel, France and Britain secretly agreed on a coordinated military sequence in the Protocol of Sèvres.
Nationalization and canal access were separate issues
Nationalizing the company was not the same act as closing the Canal to Israeli shipping. Egypt’s restrictions predated nationalization: in 1951 the UN Security Council adopted Resolution 95, calling Egyptian seizures of cargoes bound for Israel an abuse of the right of visit and search and urging an end to restrictions on international shipping. After nationalization, the Security Council adopted principles for canal operation in October 1956, including free and open transit without discrimination. The dispute over ownership of the operating company and the dispute over navigation must be kept distinct.
Israel also faced Egypt’s closure of the Straits of Tiran to Israeli shipping and attacks by fedayeen from the Egyptian-controlled Gaza Strip. These were central Israeli security concerns, separate from British and French objections to Nasser’s control of the Canal.
What the Sèvres Protocol planned
At Sèvres, France, from 22 to 24 October, Israeli, French and British representatives secretly coordinated their actions. The protocol dated 24 October said Israel would begin a major operation against Egyptian forces on 29 October, advancing toward the Canal. Britain and France would then demand that both sides withdraw from the Canal zone and that Egypt accept Anglo-French troops at key positions. If either government rejected the demands after 12 hours, the two powers would intervene.
Israel launched its attack on 29 October. Britain and France issued their ultimatum on 30 October, then attacked Egyptian airfields on 31 October and landed troops near Port Said on 5 November. The public justification was to separate the combatants and protect canal shipping; the secret protocol shows that the sequence had been agreed in advance. See why Israel went to war for the Israeli security context.
Why the intervention stopped
The United States and Soviet Union both pressed for a ceasefire, though for different strategic reasons. The UN General Assembly demanded a ceasefire and withdrawal and established the United Nations Emergency Force (UNEF). Britain and France halted their operation and withdrew by December. Israel completed its withdrawal from Sinai and Gaza by March 1957 after negotiations over shipping through Tiran and the deployment of UNEF.
The outcome exposed the political failure of Britain and France to retain control of the Canal or remove Nasser, despite their military intervention. Egypt retained national control of the company, while Israel’s campaign achieved a temporary reopening of the Straits of Tiran. That opening depended on the postwar arrangement and did not prevent Egypt from closing the straits again in 1967. The military sequence is covered in Operation Kadesh.