In April 1969, Iran abrogated the 1937 treaty over the Shatt al-Arab, and as such, ceased paying tolls to Iraq when its ships used the waterway.[1] Iran's abrogation of the treaty marked the beginning of a period of acute Iraqi-Iranian tension that was to last until the 1975 Algiers Agreement.[2] In 1969, Saddam Hussein, Iraq's deputy prime minister, stated: "Iraq's dispute with Iran is in connection with Khuzestan, which is part of Iraq's soil and was annexed to Iran during foreign rule."[3]