Secretary of State Colin L. Powell said Thursday that the United States would soon begin "intensive discussions" with Islamic countries to explore Saudi Arabia's proposal to mobilize Muslim troops to help stabilize Iraq.

He described the Saudi proposal, outlined over the past two days in talks with Saudi and Iraqi officials in the Saudi port city of Jiddah, as "an interesting idea, a welcome idea."

The United States had tried without success to persuade Islamic countries to join the multinational military force in Iraq. But Powell said the concept of a Muslim force from Middle Eastern and other countries is now more viable because two basic conditions have been met: The multinational force now has U.N. approval, and the United States handed over political power to an interim Iraqi government a month ago. He cautioned, however, that several key points still need to be explored.

"The Saudis have indicated some conditions that would have to be met, as they see it, with respect to chain-of-command arrangements, with respect to what troops would be doing, whether it would be an offset to existing coalition troops in the country," Powell said in Jiddah, where he met with Iraqi Prime Minister Ayad Allawi for the first time.

Powell said Iraq, the United States, members of the U.S.-led military coalition, the United Nations and any Muslim nations that volunteer troops still must sort out whether a new Muslim force would be part of the existing coalition, be part of a new force that would protect U.N. personnel in Iraqor be entirely separate.

Saudi Arabia envisioned putting Muslim troops under a chain of command that would be headed by the United Nations. Allawi, who has been trying for the past month to attract troops from other Muslim nations, has called for them to become part of the multinational force now in Iraq.

Allawi said he had already received some favorable responses to letters he wrote to Muslim countries shortly after he took office. Iraqi officials traveling with Allawi said Bahrain, Bangladesh, Egypt, Morocco, Oman, Pakistan and Tunisia were among the countries he approached.

Iraq's government and the prospective volunteers now "have to expand discussion on what kind of commitment they should have," Allawi said. "This is something we will pursue in the weeks ahead. I will be talking to some of them in the next few days to try and find the common ground."

Allawi conceded that troops from Arab and other Muslim countries might be as vulnerable as coalition troops to attacks by insurgents, but he said the Islamic world needs to take a united stand against terrorism.

"These are forces of evil who are acting against us. We are going to suffer casualties," Allawi said. "There is no other route. I call upon the leaders of the Islamic countries and the Arab countries to close rank because this is basically our fight."

The insurgents, Allawi said, "are people who claim to be part of Islam, and they are not. They claim to be part of the Arabs, and they are not."

Pakistan, which has one of the largest and best-trained armies in the Islamic world, may be considering committing troops to Iraq, according to news service reports.

Indonesia, the world's most populous Muslim country, said Thursday it would consider sending troops as part of a U.N. peacekeeping force but not to help quell the insurgency.

"We certainly won't entertain the idea of having our troops there as part of a multinational force unless it is under a U.N. framework," said Marty Natalegawa, a spokesman for Indonesia's Foreign Ministry. "That is the only possible scenario within which we will operate."

Hanging over the Saudi proposal is a new threat issued by an organization calling itself the Islamic Tawhid Group, which threatened all Islamic nations that decide to send troops to Iraq. "We will not remain silent if troops are sent to Iraq by any Arab or Muslim country, especially by Saudi Arabia, Pakistan, Egypt and others," it said in a statement posted Thursday on an Islamic Web site. "We will strike with an iron fist all the traitors of Arab governments who cooperate with the Zionists."

Correspondent Ellen Nakashima in Jakarta, Indonesia, contributed to this report.