Prime ministership of Mir-Hossein Mousavi secret negotiations and dealing with USA on helping them free the American hostages in Lebanon, in return for sale of the American weapons and spare-parts that Iran's army badly needed for Iran–Iraq War. Shortly after the end of Iran–Iraq War on 20 August 1988, Ruhollah Khomeini died, and Ali Khamenei was elected as the new Supreme Leader by the Assembly of Experts. Following his death, Mousavi and his fellow left-wingers lost their main source of support within the establishment. During the parliament hearing on post-war reconstruction plans, Mousavi had heated arguments with Ali Akbar Hashemi Rafsanjani, the speaker of Iran's
2009 Iranian presidential election movement attempted to unite behind a single candidate; former President Mohammad Khatami was the leading opponent to Ahmadinejad in some opinion polls, until he withdrew and endorsed former Prime Minister Mir-Hossein Mousavi. Former Speaker of the Majlis Mehdi Karroubi, another Reformist, was also running; as was the former commander of the Iranian Revolutionary Guard, Mohsen Rezaee, a conservative with a reputation for political pragmatism. The election marked a return to public spotlight for Mousavi, who had not received much attention since he served as Prime Minister in the 1980s. Reformist opinions galvanized around him as the election grew nearer. He