Ups and downs of Iraq-Iran relations

FACTBOX-Ups and downs of Iraq-Iran relations

Feb 28 (Reuters) - The first visit to Iraq by an Iranian president since the 1979 Islamic revolution aims to boost ties with a country with which Iran fought an eight-year war in the 1980s and show the United States that Tehran cannot be ignored.

Tehran's influence over Baghdad has grown since the U.S.-led invasion that toppled Iran's long-time enemy Saddam Hussein in 2003.

Following are details about relations in the past 20 years:

* IRAN-IRAQ WAR:

-- September 1980 - Iraq accused Iran of shelling Iraqi border towns from territory belonging to Iraq under the 1975 Algiers accord on frontier line and Shatt al-Arab waterway. Saddam Hussein tore up the accord and his troops invaded Iran.

-- March 1988 - Iran seized the town of Halabja in northeast Iraq. Tehran said Iraq used chemical weapons to punish inhabitants for not resisting. Around 5,000 people were killed.

-- August 1988 - The Middle East's longest armed conflict in modern times ended with a U.N.-sponsored ceasefire. Around 1 million people were killed in a conflict which involved trench warfare, chemical attacks and mass Iranian frontal assaults.



* GULF WAR:

-- August 1990 - Iraq invaded Kuwait. Days later Saddam told Iran he would withdraw from occupied Iranian territory and formally settle the 1980-88 war.

-- January 1991 - Iraq flew more than 140 aircraft to Iran to avoid their destruction before a U.S.-led attack to force Iraqi troops out of Kuwait. Iraq's air force commander said in 2007 he hoped Iran would return some Iraqi warplanes.



* IMPROVING TIES

-- 1998 - Iran's moderate president, Mohammad Khatami, broke a logjam in ties, leading to swapping more prisoners from the 1980-88 war and relaunching pilgrimages by Iranians to holy Shi'ite Muslim sites in Iraq.

-- 2003 - Iran-Iraq ties improve after Saddam Hussein was toppled. The invasion led to an Iraqi government led by Shi'ites, Iran's dominant religion, coming to power.

-- The U.S. military has accused Iran of stoking violence in Iraq by funding, training and equipping militias. Iran denies this, blaming the presence of U.S. troops for the violence but analysts have said Iran has seen Iraq as a useful lever.

-- More recently Iran may have used its influence with Shi'ite militias to help reduce violence as a concession to Washington when Tehran was worried about a U.S. threat to resort to force to deal with a nuclear row.

-- Iraq has also credited Tehran with helping rein in the Mehdi Army militia of Shi'ite cleric Moqtada al-Sadr.



* EXILES:

-- 1978 - Ayatollah Ruhollah Khomeini spent several years in exile in the Iraqi city of Najaf before launching Iran's 1979 Islamic revolution that rattled the Sunni-dominated Arab world.

-- Several Iraqi politicians spent years in exile in Iran when Saddam was in power, including the head of Iraq's biggest Shi'ite party, Abdul Aziz al-Hakim, and Jalal Talabani, a Kurd who is now the Iraqi president. (Writing by David Cutler, London Editorial Reference Unit)