OFFICERS SAY U.S. AIDED IRAQ IN WAR DESPITE USE OF GAS

A covert American program during the Reagan administration provided Iraq with critical battle planning assistance at a time when American intelligence agencies knew that Iraqi commanders would employ chemical weapons in waging the decisive battles of the Iran-Iraq war, according to senior military officers with direct knowledge of the program.

Those officers, most of whom agreed to speak on the condition that they not be identified, spoke in response to a reporter's questions about the nature of gas warfare on both sides of the conflict between Iran and Iraq from 1981 to 1988. Iraq's use of gas in that conflict is repeatedly cited by President Bush and, this week, by his national security adviser, Condoleezza Rice, as justification for ''regime change'' in Iraq.

The covert program was carried out at a time when President Reagan's top aides, including Secretary of State George P. Shultz, Defense Secretary Frank C. Carlucci and Gen. Colin L. Powell, then the national security adviser, were publicly condemning Iraq for its use of poison gas, especially after Iraq attacked Kurds in Halabja in March 1988.