evidence: Core issue: Political antagonism between the Iraqi and Iranian governments, and territorial disputes over the province of Khuzestan and the Shatt al-Arab river [...] The Iran-Iraq war was initiated on September 22, 1980, after Iraq's invasion of Iran. With the attack, Saddam Hussein intended to seize the Iranian province of Khuzestan and the east bank of the Shatt al-Arab River. Contributing to the decision was also Saddam's distrust of Iran's post-1979 government. [...] After almost two years of talks, and mainly because of Iraq's concession, both countries came to an informal agreement to reestablish the previous terms of the 1975 Treaty Concerning the State Frontier and Neighbourly Relations between Iran and Iraq. This move was followed by the normalization of diplomatic relations, an agreement on the use of the Shatt al-Arab River and an agreement concerning a prisoner exchange, which was only finalized in 2003. The conflict resolution process is considered as peaceful thawing.