As a special envoy for the Reagan administration in 1984, Donald H. Rumsfeld, now the defense secretary, traveled to Iraq to persuade officials there that the United States was eager to improve ties with President Saddam Hussein despite his use of chemical weapons, newly declassified documents show.

Mr. Rumsfeld, who ran a pharmaceutical company at the time, was tapped by Secretary of State George P. Shultz to reinforce a message that a recent move to condemn Iraq's use of chemical weapons was strictly in principle and that America's priority was to prevent an Iranian victory in the Iran-Iraq war and to improve bilateral ties.

During that war, the United States secretly provided Iraq with combat planning assistance, even after Mr. Hussein's use of chemical weapons was widely known. The highly classified program involved more than 60 officers of the Defense Intelligence Agency, who shared intelligence on Iranian deployments, bomb-damage assessments and other crucial information with Iraq.

The disclosures round out a picture of American outreach to the Iraqi government, even as the United States professed to be neutral in the eight-year war, and suggests a private nonchalance toward Mr. Hussein's use of chemicals in warfare. Mr. Rumsfeld and other Bush administration officials have cited Iraq's use of poisonous gas as a main reason for ousting Mr. Hussein.