The Turkish foreign minister announced yesterday that his nation will not participate in an attack against Iraq, a move that reflects a recent unpublicized agreement between Turkey and Iran that neither will move against the neighboring forces of Iraqi President Saddam Hussein.

Arab and Western diplomats said the deal struck by the Turkish and Iranian foreign ministers at a Jan. 4 meeting in Islamabad has the effect of ruling out a ground attack against Iraq from anywhere besides Saudi Arabia. This will force U.S. and allied troops stationed in Saudi Arabia to shoulder the burden of any military offensive, the officials said.

Turkish Foreign Minister Kurtcebe Alptemocin told his country's parliament last night that the country would not open a second war front against Iraq, but made no mention of the deal with Iran. He also said a contingent of U.S. and allied planes recently sent to Turkey would be used only for defensive purposes.

The diplomats, who spoke on condition they not be identified, said Turkish and Iranian officials negotiated the arrangement in order to remove any threat that either nation would conquer and keep some of Iraq's territory. They said Turkish President Turgut Ozal had informed President Bush of the decision.

"Turkey will keep quiet . . . to keep the Iranians quiet," one source explained. "If Turkey moves, others might."

Shortly after Iraq's Aug. 2 invasion of Kuwait, some U.S. officials said they hoped that Turkey would consider participating in an attack on Iraq or allowing an attack by others to be mounted from Turkish territory. But Turkish officials last week rejected an appeal from Secretary of State James A. Baker III for permission to launch U.S. air strikes against Iraq from military bases on Turkish soil.

Turkey agreed, however, to allow U.S. planes to use its air bases after completing strikes in Kuwait and Iraq -- an arrangement seen as less "provocative" to Iraq and less politically troublesome at home, the officials said. Turkey is a Moslem country sensitive to the danger of long-term damage to its previously good relations with Iraq, particularly in trade and managing of Kurdish separatists.

The arrangement will allow U.S. planes that hit targets in northern Iraq to be refueled in or over Turkish territory, but will force them to fly to aircraft carriers or military bases in Egypt and other countries for rearmament, U.S. military officials said.

Informed Western officials say Turkey has 120,000 to 150,000 troops on its 150-mile border with Iraq, partly accounting for Iraq's deployment of roughly 100,000 troops in the area. A U.S. official said some of the Iraqi forces are also intended to control potentially rebellious ethnic Kurds in the area.

Iran has also shown no interest in attacking Iraq, although it has formally collaborated in the U.N.-sanctioned embargo of Iraqi trade. The Tehran government announced last week that it would soon begin its first extensive maneuvers of ground troops along the Iraqi border since it signed a peace treaty with Iraq Sept. 10.

The diplomatic officials said Turkey and Iran have also agreed to work together to block renewed efforts by Kurdish separatists to gain greater autonomy within Iraq's borders after the end of a war. Experts say there are 3 million to 4 million Kurds in Iraq, another 4 million to 5 million in Iran and about 10 million in Turkey.

Laurie Mylroie, a Middle East expert at Harvard University, said Kurdish claims in Iraq partly stem from a promise by the victors in World War I for a separate Kurdish state or political autonomy.

Special correspondent John Murray Brown in Ankara contributed to this report.