GENEVA, JAN. 9 -- Six-and-a-half hours of intense talks between Secretary of State James A. Baker III and Iraqi Foreign Minister Tariq Aziz over the Persian Gulf crisis failed to break the diplomatic impasse tonight as Iraq showed no signs of buckling to international demands that it relinquish Kuwait immediately and unconditionally.

"Regrettably," a somber Baker announced, "I heard nothing that suggested to me any Iraqi flexibility whatsoever." Aziz renewed Iraqi demands for a settlement of the broader Middle East conflict and declared that Iraq would "absolutely" attack Israel if the multinational forces on the Arabian Peninsula move against Iraqi troops in Kuwait.

The deadlock here could bring the massive armies closer to war, but it also appeared to trigger a fresh spurt of diplomatic initiatives in the six days remaining before the Jan. 15 U.N. deadline for Iraq to pull out of Kuwait. President Bush and Baker backed a visit by U.N. Secretary General Javier Perez de Cuellar to Baghdad, just days after discounting the idea of such a mission, and Aziz said he would be welcome. Perez de Cuellar accepted the invitation tonight.

The collapse of the talks came at the end of a riveting day of international diplomacy played out at the Intercontinental Hotel here. The talks extended for many more hours than had been expected, raising initial hopes of a breakthrough, and then fell into recriminations from all sides that were televised around the globe in consecutive appearances by Baker, Aziz and Bush.

They described in stark detail how the two sides had, in calm discussions across a rectangular table, failed to discover any common ground, and how Baker had presented Aziz with a letter from Bush to Iraqi President Saddam Hussein, which the Iraqi foreign minister read and then refused to accept. An Arabic translation of the letter also was rejected in Washington by Iraqi Ambassador Mohamed Mashat.

Bush declared, "This is but one more example that the Iraqi government is not interested in direct communications designed to settle the Persian Gulf situation. The record shows that whether the diplomacy is initiated by the United States, the United Nations, the Arab League or the European Community, the results are the same, unfortunately. The conclusion is clear: Saddam Hussein continues to reject a diplomatic solution." Bush described Aziz's response to Baker as "a total stiff-arm, a total rebuff." But, Bush added, "I have not given up on a peaceful outcome. It's not too late."

According to officials involved in preparing the letter to Saddam, it appealed to him in direct terms to withdraw from Kuwait and described the consequences for his regime of failing to do so, including strong language about the military capability of the alliance to force Iraq out of Kuwait. Aziz said he objected to the tone, which he said was harsher than Baker's presentation.

Although both sides expressed hope for a last-minute resolution, the collapse of the talks also brought signs that war may be drawing closer. French President Francois Mitterrand announced that if Iraq fails to meet the U.N. deadline he will call Parliament into session to vote a declaration approving the terms of French participation in a military operation to liberate Kuwait, but not to go further and attack Iraq.

Baker immediately adjusted his schedule, delaying a planned trip to Turkey so he can rush to Riyadh for talks with Saudi Arabia's leadership. Baker announced that he had asked for and received assurances from Aziz that American diplomats at the U.S. Embassy in Baghdad would be permitted to depart Jan. 12, removing them from harm's way should a massive attack be launched against Iraq. Baker said the Iraqi Embassy in Washington would cut back its staff but that a few diplomats could remain.

Baker and Aziz, flanked by seven advisers and a translator each, met in a conference room at the hotel. They broke for lunch and Baker called Bush in Washington; he later reported to Bush again when the talks ended.

Summarizing his presentation to Aziz, Baker told hundreds of reporters from around the world who gathered here, "There have been too many Iraqi miscalculations. The Iraqi government miscalculated the international response to the invasion of Kuwait, expecting the world community to stand idly by while Iraqi forces systematically pillaged a peaceful neighbor. It miscalculated the response . . . to the barbaric policy of holding thousands of foreign hostages, thinking that somehow cynically doling them out a few at a time would somehow win political advantage, and it miscalculated that it could divide the international community and gain something thereby from its aggression."

"So let us hope that Iraq does not miscalculate again," Baker added. "The Iraqi leadership must have no doubt that the 28 nations which have deployed forces to the gulf in support of the United Nations have both the power and the will to evict Iraq from Kuwait."

Baker said that Aziz had not explicitly rejected the appeals to withdraw from Kuwait, but he had heard nothing in the talks to indicate a willingness to do so.

As expected, Baker said he had promised Aziz that the United States would not attack if Iraq complied with the 12 U.N. resolutions and pulled out of Kuwait. He noted that Bush had said, "We do not desire nor want a permanent military ground presence" in the Persian Gulf.

Questioned whether he and Bush had made an adequate effort to make diplomacy work with Iraq before going to war, Baker replied, "The truth of the matter is, we have been very . . . responsible and measured in our approach to this. We have not, as some might suggest, gone off half-cocked."

"So I think there's been more diplomacy exercised in this crisis than in almost any that I can think of," Baker said. "And the one thing I would ask you all not to do is to equate diplomacy and appeasement. We made that mistake in the 'thirties. At least for our part, we don't intend to make it again."

Aziz, recounting at length his conversations with Baker, described Iraq's interests in terms of a broad Middle East peace settlement, and he dodged questions about the seizure of Kuwait. He refused to discuss "allegations" about atrocities in Kuwait and insisted Iraq had "historic rights" regarding its much smaller neighbor.

Aziz repeatedly cast Iraq as a persecuted nation, targeted by the United Nations only because of pressure from the United States and singled out for punishment by Washington even before it invaded Kuwait. He lashed out at what he called the "double standard" of U.S. support for Israel while not insisting on implementation of the U.N. resolutions calling for Israel to relinquish territories it occupies. Aziz said Saddam had drawn support from Palestinians and others treated unfairly in the Arab world.

Aziz was defiant when asked if Iraq would attack Israel in response to any attack from the alliance. "Yes," he said calmly. "Yes, absolutely."

If war breaks out, he said, "Iraq will defend itself in a very bold manner." He added, "We deeply feel we have been treated unjustly."

Point by point, Aziz and Baker appeared to have patiently aired their differences and found no way to bridge them. Their separate accounts of the meetings largely agreed on the facts of what had been said -- and painted a picture of many hours of discussion that had gone nowhere. It began when Baker presented Bush's letter and Aziz handed in back because, he said, he did not like the tone, and it ended 6 hours and 27 minutes later when, Baker said, the two ministers had nothing more to say.

Aziz raised the possibility of an international conference on the Middle East; Baker said that "rewarding Iraq's aggression with a link to the Arab-Isreali peace process would really send a terrible signal." Aziz said Iraq was seeking to help the Palestinians; Baker said Iraq invaded Kuwait for its "own aggrandizement."

Baker raised with Aziz concerns in the West about Iraq's quest for weapons of mass destruction -- nuclear, chemical and biological arms. Aziz responded by saying that Iraq would be willing to eliminate all such weapons from the region, and cited Israel as the other state with nuclear arms. Aziz said he told Baker, "My guess is you cannot get such a pledge" from the Israeli leadership.

Likewise, while Baker wanted to focus on the plight of Kuwait, Aziz sought to turn attention to other regional issues.

"I heard some things that I quite frankly found very hard to believe," Baker said. "I heard, for instance, that their action in invading Kuwait was defensive in nature, that they were being threatened by Kuwait. . . . I find it hard to believe that any nation in the world will believe that."

Aziz said he again would extend an invitation to Baker to come to Baghdad and talk with the Iraqi leadership, but Baker firmly rejected it again.

Baker said he warned Aziz not to "miscalculate the resolve of the American people" to go to war. Aziz said he had dealt with the subject at length in the talks and told Baker that he had listened to Bush's and Baker's many statements on Cable News Network and found nothing new in their presentation to him today.

Going into today's meeting, U.S. officials had low expectations for a breakthrough, largely because of weeks of fruitless jockeying with Baghdad over dates for the encounter. American officials have said they became convinced in recent weeks that Saddam was trying to use the prospect of diplomacy to forestall an attack, a conclusion some said was reinforced by the outcome tonight.

The meeting also had roots in Bush's decision Nov. 8 to nearly double the size of the U.S. force in Operation Desert Shield. The decision, announced after virtually no consultation with Congress, angered many on Capitol Hill who felt Bush was sliding toward war. After the U.N. Security Council, in late November, approved a resolution authorizing the use of force against Iraq, Bush, consulting just a handful of top advisers, including Baker, announced an overture for meetings with Iraq.

That overture was originally for meetings before Jan. 15, later narrowed to 15 dates in late December or early January. Iraq refused to agree to the dates proferred by the White House, and proposed Jan. 12, which Bush rejected as being too close to the deadline to allow serious talks. Under renewed pressure to give diplomacy a chance, Bush agreed on today's session.