ANKARA -- NATO member Turkey will host a summit Thursday of the foreign ministers of key regional players Egypt, Iran, Jordan, Saudi Arabia and Syria as part of last-ditch efforts for a peaceful end to the Iraq standoff.

Turkish Foreign Minister Yasar Yakis announced the initiative on Tuesday, adding that heads of state and government of the six Muslim nations, five of which border Iraq, could also convene later depending on the outcome of the Istanbul gathering.

The announcement came as the leader of Turkey's ruling Justice and Development Party renewed calls on the United States to refrain from starting a new military confrontation in the conflict-ridden Middle East.

"We call on the conscience of the world so that the process which began as the struggle against terrorism is not blown out of proportion," Recep Tayyip Erdogan said in a speech before Parliament.

"We believe that all the global decision-makers must heed the increasing demands for peace all over the world for the future of humanity and civilization," Erdogan said.

His appeal followed a harsh outburst by U.S. Defense Secretary Donald Rumsfeld, who hinted that diplomatic efforts in the Iraq crisis were failing to bear fruit.

"In the case of Iraq, we're nearing the end of the long road, and with every other option exhausted," Rumsfeld said Monday.

The crisis between Baghdad and Washington has put Turkey, the only Muslim member of NATO, in a delicate situation.

The country, which is home to major military facilities, is under pressure to provide support for a possible U.S. operation against Iraq, but fears that turmoil there could deal a blow to its already crisis-hit economy and spark unrest on both Kurdish-populated sides of the Turkish-Iraqi border.

Ankara proposed the regional summit last week following a Middle East tour by Prime Minister Abdullah Gul aimed at exploring ways of averting war.

Following talks with Turkish officials here Monday, U.S. military chief Richard Myers expressed confidence in Washington's "strategic partnership" with Turkey.

Myers denied that Washington was growing impatient with Ankara's reluctance to back military options against its southeastern neighbor.

Ankara is under pressure to allow U.S. troops to use Turkish air bases for a possible intervention to topple Saddam Hussein and to agree to the deployment of U.S. soldiers on Turkish soil, which they could use as a springboard for intervention in northern Iraq.

Any such decision, which requires parliamentary approval, could prove damaging for the government, which was elected only in November and is facing a staunch anti-war public opinion.

The Istanbul summit is expected to result in a joint declaration putting pressure on Baghdad to take firmer steps to convince Washington of its commitment to disarm.

The meeting "will concentrate on efforts that might spare Iraq from military strikes," Egyptian Foreign Minister Ahmed Maher said at a press conference with his Saudi counterpart Prince Saud al-Faisal in Cairo. Maher said earlier that the talks "could amount to a last chance for a peaceful settlement of the iraqi crisis."

Speculation has also been rife that the leaders of the six nations could consider an exile formula for Saddam Hussein.