SHANNON, IRELAND, NOV. 3 -- Secretary of State James A. Baker III headed for the Persian Gulf and Europe today to lay the groundwork for a new United Nations Security Council resolution authorizing the use of force against Iraq and to ask Arab and European allies under what conditions they would support military action.

The United States, Baker told reporters accompanying him, "has made it extraordinarily clear" to Iraqi President Saddam Hussein that it is prepared to use force if the crisis cannot be resolved peacefully.

The threat of armed conflict is "not just words," Baker said, echoing the hard line taken in recent days by President Bush.

Despite the strong language, administration officials said any decision by Bush about the need for military action is not likely for some weeks, perhaps until next month, as long as there is no provocation from Saddam.

While refusing to discuss specific military options, Baker said: "We've got questions for our coalition partners. We'd like to know under what conditions and subject to what constraints they'd be willing to consider certain types of action."

According to other administration officials, one of the key questions Baker wants to have answered is whether the coalition partners are prepared to pay a high price in casualties if conflict breaks out.

Some Arab diplomats in Washington have speculated that the conflict could largely be fought from the air, with heavy allied bombing sparing ground troops from severe casualties. Baker, one official said, does not believe this scenario and thinks that a war could inflict a heavy toll, and he wants to get a first-hand understanding of whether Arab leaders with forces in the region are prepared to make such a sacrifice.

In Baghdad, an Iraqi official suggested today that all foreign hostages might be released if two of a list of five major countries declared their non-belligerency. Asked about the apparent diplomatic initiative, Baker replied, "There are a lot of things that are sort of being run up the flagpole, so let's wait and see." He did not elaborate, but seemed to indicate that the United States regarded the proposal as not serious. {Story on Page A32.}

Baker said he would have discussions on this trip with the other four permanent members of the Security Council -- Britain, France, China and the Soviet Union -- about possible action this month on a resolution authorizing the use of force. Baker said he also would consult with other alliance partners about how long to apply economic and political pressure before considering military action.

Administration officials said Baker and other advisers to Bush would like to "calibrate" an escalation of the pressure on Saddam over the next several weeks. This effort involves public expressions of impatience, threats of force and private preparations that would be necessary prior to conflict.

Baker is scheduled to see King Fahd of Saudi Arabia and President Hosni Mubarak of Egypt. He said today that he may also meet Syrian officials while in the region.

Baker is also seeking answers to difficult, unresolved questions about the command and control of allied forces if conflict erupts.

At the same time, Baker made it clear today that he hopes to use other methods to increase pressure on Saddam, short of actual conflict in the weeks ahead.

The United States, he said, would seek to implement the latest Security Council resolution calling for resupply of the U.S. and British embassies in Kuwait.

Baker said he will ask coalition members about extending economic sanctions and about support for states in the front line of the embargo. "We need to know the extent and degree to which countries are willing to support this joint and mutual effort as it moves forward and as the time frame becomes one of, let's say, months rather than weeks," he said.

Reflecting the new, more intense phase of the crisis, Baker brought with him today a number of senior administration officials from outside the State Department, including Paul Wolfowitz, undersecretary of defense for policy; Richard Haass, Middle East specialist on the National Security Council staff, and Lt. Gen. Howard Graves, assistant to the chairman of the Joint Chiefs of Staff. Underscoring his concern about congressional anxiety over the crisis, Baker's entourage also includes Janet G. Mullins, assistant secretary of state for legislative affairs.

"The overall purpose of the trip is to discuss with our coalition partners strengthening the full range of measures that we have employed to isolate Saddam Hussein -- political measures, economic measures and military measures," Baker said, "and thereby to lay a foundation for the possible future exercise of all options. This will improve the prospects of a peaceful resolution and at the same time permit us to be prepared to consider all options if peaceful ones don't work."

Questioned whether the recent U.S. threats to use force have been getting through to Saddam, Baker said, "You're dealing with someone who is very difficult to predict. So I can't read his mind. I think we've made it extraordinarily clear that we are unwilling to rule out the use of force. I think most people believe that, based on what they've heard and, most of all, based on what they've seen of the actions the U.S. has taken."

Baker ruled out the dispatch of any special American envoy to Iraq at this point, saying the U.S. Embassy in Baghdad continues to have contacts with Iraqi officials.

Questioned about the possible Security Council resolution authorizing the use of force, Baker said the United States believes it has the "requisite authority" for military action without prior United Nations approval, citing Article 51 of the United Nations Charter allowing "collective self-defense" of other nations.

Some legal experts have questioned this approach, but the administration says existing requests for aid from Kuwait and Saudi Arabia would be sufficient legally. Baker emphasized, however, that the president "would like to maintain as much of the international consensus as he can."

Baker said preliminary talks with Soviet Foreign Minister Eduard Shevardnadze on the possible U.N. resolution were held last month in New York. The Soviets have repeatedly said they want to avoid a military solution, and Baker's meetings with Shevardnadze and Soviet President Mikhail Gorbachev next Thursday in Moscow are expected to focus in part on Moscow's reaction to such a new resolution. The United States hopes to avoid a veto by any of the five permanent members. China, a member of the five, is expected to abstain but not veto the resolution, a diplomatic source said.

The United States serves as president of the Security Council this month, and Baker said "there's still a host of resolutions that could be looked at" to press Saddam before a decision about military action must be made.

Baker was scheduled to arrive early Sunday in the Persian Gulf emirate of Bahrain.