In October 1945, Mollet was elected to the National Assembly for Pas-de-Calais. The following year he became Secretary-General of the French Socialist Party and served as a minister in the government headed by Leon Blum in 1946.
Mollet became prime minister of a coalition government in January 1956. Later that year President Gamal Abdel Nasser of Egypt announced he intended to nationalize the Suez Canal. The shareowners, the majority of whom were from Britain and France, were promised compensation. Nasser argued that the revenues from the Suez Canal would help to finance the Aswan Dam.
Anthony Eden, the British prime minister, feared that Nasser intended to form an Arab Alliance that would cut off oil supplies to Europe. On 21st October, 1956, Mollet, Anthony Eden and David Ben-Gurion met in secret to discuss the problem. During these talks it was agreed to make a joint attack on Egypt.
On 29th October 1956, the Israeli Army, led by General Moshe Dayan, invaded Egypt. Two days later British and French bombed Egyptian airfields. British and French troops landed at Port Said at the northern end of the Suez Canal on 5th November. By this time the Israelis had captured the Sinai peninsula.
President Dwight Eisenhower grew increasingly concerned about these developments. On 30th October he decided to take action and announced he was going to suspend aid to Israel in protest against its invasion of Egypt. The following day Eisenhower's secretary of state, John Foster Dulles, criticised Britain and France for trying to take the Suez Canal by force.
On 1st November representatives from the United States and the Soviet Union at the United Nations joined forces and demanded a cease-fire. The British and French vetoed a cease-fire in the Security Council but the General Assembly passed it by a vote of 64-5 vote. Faced by a united international community, the governments of Britain, France and Israel agreed to withdraw. They were then replaced by UN troops who policed the Egyptian frontier.
Gamal Abdel Nasser now blocked the Suez Canal. He also used his new status to urge Arab nations to reduce oil exports to Western Europe. As a result petrol rationing had to be introduced in several countries and two months after the invasion, Anthony Eden was forced to resign from office. Guy Mollet and his government collapsed in May 1957.
Over the next fourteen years Mollet attempted to organize a unified socialist opposition. However, unable to regain power, Mollet retired from public life in 1971.
Guy Mollet died in 1975.
Eden and Lloyd went to Paris to meet the French. Eden accepted pressure from the French Premier, Guy Mollet; Lloyd was desperately worried. Mollet and Ben-Gurion, the Israeli Prime Minister, met at Sevres. They were joined by a 'responsible British minister', identity not disclosed, but said to be 'an old-fashioned family lawyer' - it was, in fact, a still unhappy Selwyn Lloyd. The plan was for Israel to attack Egypt, and then for Britain and France to appeal for a cease-fire and to intervene in the isthmus.
At the meeting in France on 1 October, there was still doubt whether Britain would join in, yet her bombers, a component in which France was deficient, were essential to the operation. The second meeting took place in Paris on 21 October. The proposal put to the Israelis was that Britain and France would demand that both Egypt and Israel should withdraw from the Canal area. If either refused, Britain and France would intervene to keep the Canal open. The plan was that Israel should attack the Canal zone while Britain and France should go in as policemen, demanding Israel's and Egypt's withdrawal, and would then take over the Canal.
The Governments of the United Kingdom and France have taken note of the outbreak of hostilities between Israel and Egypt. This event threatens to disrupt the freedom of navigation through the Suez Canal on which the economic life of many nations depends. The Governments of the United Kingdom and France are resolved to do all in their power to bring about the earliest cessation of hostilities and to safeguard the free passage of the Canal.
They accordingly request the Government of Israel to stop all warlike action on land, sea and air forthwith; to withdraw all Israeli military forces to a distance of ten miles east of the Canal.
The communication has been addressed to the Government of Egypt, requesting them to cease hostilities and withdraw their forces from the neighbourhood of the Canal and to accept the temporary occupation by Anglo-French - forces of key positions at Port Said, Ismailia and Suez.
The United Kingdom and French Governments request an answer to this communication within twelve hours. If at the expiration of that period one or both Governments have not undertaken to comply with the above requirements, the United Kingdom and French forces will intervene in whatever strength may be necessary to secure compliance.