'Support': Secret documents reveal that former President Ronald Reagan's administration acquiesced in Iraq's use of chemical weapons

The United States helped Saddam Hussein attack Iran with chemical weapons in the 1980s during the Iran-Iraq war, it has been claimed.

Ronald Regan's administration, who supported the Iraqi dictator topple two decades later by the Bush government, fed information to Baghdad that helped them launch strikes.

U.S. officials gave Saddam's army details about the whereabouts of Iranian forces in 1988 knowing that he would deploy chemical weapons, Foreign Policy magazine reported.

Iraq used mustard gas and sarin in early 1988 in four major offensives which helped bring about the end of the eight-year conflict.

During the whole war, up to 20,000 Iranian troops were killed by mustard gas and nerve agents from Iraq and 100,000 were wounded.

They were able to launch the strikes after being given maps, satellite pictures and other intelligence by the U.S.

The Americans have always said that Iraq did not reveal that they would launch chemical strikes.

But documents released in the National Archives and interviews with former serviceman show that the U.S. acquiesced in the use of chemical weapons as they tried to help Saddam with the war.

Retired Air Force Colonel Rick Francona, a military attache who was working in Baghdad in 1988, told Foreign Police magazine said that they knew what Saddam was planning.

'The Iraqis never told us that they intended to use nerve gas. They didn't have to. We already knew," he told Foreign Policy.

Official documents revealed that the U.S. officials were given detailed information about the use of nerve gas by the Iraqis during the conflict. They indicate that the Americans knew more about Saddam's use of chemical weapons than previously thought.

The CIA's Director of Central Intelligence William J Casey was given detailed intelligence about the efforts of Iraqi chemical weapons plants to produce mustard gas for troops.

The cache of newly-released documents also revealed that the Americans feared the Iranians may launch terror strikes against the U.S. around the world if they had evidence to suggest the Ronald Reagan's administration acquiesced in Saddam's use of chemical weapons.

One secret document from September 1984, headed 'The Islamic bomb: Chemical rather than nuclear?', revealed the scale of Iraq's chemical weapons programme.

It said: 'Iraq has over the last several years developed a substantial CW (chemical weapons) production capability.

'CIA presently estimates that Iraq is capable of producing at least two tons per day of the nerve agent.'

Another document, marked 'Top Secret' from January 1985, indicated that the Iraqis would use chemical weapons against Iran.

It said: 'The Iraqis have used chemical weapons in three separate battles beginning in August 1983 and will use chemical weapons on a wide scale in the event of another major Iranian attack.'

The Geneva Protocol of 1925, which the Americans had ratified in 1975, states undertake that they will not use chemical weapons and agree they 'will exert every effort to induce other States' to do the same.

The CIA have not responded to a request for comment from MailOnline.