 In February 1959, Macmillan visited the Soviet Union.Talks with Nikita Khrushchev eased tensions in East-West relations over West Berlin and led to an agreement in principle to stop nuclear tests and to hold a further summit meeting of Allied and Soviet heads of government.In the Middle East, faced by the 1958 collapse of the Baghdad Pact and the spread of Soviet influence, Macmillan acted decisively to restore the confidence of Persian Gulf allies, using the Royal Air Force and special forces to defeat a revolt backed by Saudi Arabia and Egypt against the Sultan of Oman, Said bin Taimur, in July 1957; deploying airborne battalions to defend Jordan against Syrian subversion in July 1958; and deterring a threatened Iraqi invasion of Kuwait by landing a brigade group in July 1960.