RBIL, Iraq, July 6 As the United States considers ways of accomplishing President Bush's call for an end to Saddam Hussein's rule in Iraq, Washington's goal of a "regime change" in Baghdad is running into strong reservations from Iraqi Kurdish leaders who would be crucial allies in any military campaign.

These leaders, interviewed in their strongholds in northern Iraq in the last week, say flatly that they would be reluctant to join American military operations that put Kurds at risk of an onslaught by Iraqi troops of the kind they suffered after the Persian Gulf war in 1991. A Kurdish uprising then that was encouraged by the first President Bush was brutally suppressed by Mr. Hussein, and American forces failed to intervene as thousands of Kurds were killed.

No group has suffered more from Mr. Hussein's 23-year-old rule than the Kurds, who lost tens of thousands of lives to Iraqi offensives in the 1980's and 90's. The most brutal attacks, cited by the present President Bush recently as part of the justification for toppling the Iraqi ruler, involved Iraqi use of poison gas at Halabja and dozens of other towns and villages in the northern Kurdish districts during the eight-year Iran-Iraq war that ended in 1988.

Still, no Iraqis have benefited more from Western support in the last decade than the Kurds. Protected by a "safe haven" declared by the United Nations and a "no-flight zone" patrolled by American and British warplanes, the Kurds, with barely 40,000 troops and only light weapons, have built a 17,000-square-mile mini-state that arcs across a 500-mile stretch of Iraqi territory bordering Syria, Turkey and Iran.

The threat of Western airstrikes has kept Iraqi armored battalions immobilized to the south, often within artillery range of Kurdish strongholds like Erbil, a sprawling city of 750,000 people 250 miles north of Baghdad. In this "liberated area" of soaring mountains, fertile foothills and semi-desert, the Kurds have built a society with freedoms denied to the rest of Iraq's population.

The Kurdish-controlled area has opposition parties and newspapers, satellite television and international telephone calls, and an absence of the repressive apparatus that has prompted international human rights organizations to brand Mr. Hussein's Iraq a terror state.

The drawback is that all this exists outside international law, and could be made permanent only by a new government in Baghdad that embraced freedoms for all of Iraq.

But while an American-led military campaign to topple Mr. Hussein holds out the possibility of making their freedoms more secure, the Kurdish leaders, backed by almost every Kurd who discussed the issue, said Washington would be asking them to put all they have gained from their decade of autonomy at risk of a fresh Iraqi offensive.

"We are not ready to take any risks, and if we are not sure of the outcome of any step, then we are not ready to take that step, because we are not sure of improving our circumstances," Massoud Barzani, leader of one of the two main Kurdish political groups, the Kurdistan Democratic Party, said at his mountaintop headquarters outside Salahuddin, north of Erbil.

He added, alluding to the centuries of oppression Kurds suffered from Turks, Arabs and Persians, "This is a golden era for Iraqi Kurds."

Their concerns are so deep that the Kurds have set aside political differences among themselves to speak with a common voice on the possibility of American action against Mr. Hussein. After a history of internecine strife, including a brief civil war in 1996, Mr. Barzani's Kurdistan Democratic Party and Jalal Talabani's Patriotic Union of Kurdistan have divided the northern territory into two separate areas, each with its own government and army.

But at their respective headquarter cities, Erbil and Sulaimaniya, the reluctance of the Kurds to support American moves against Mr. Hussein is expressed in virtually identical terms. Leaders in both cities said officials from the Pentagon, the State Department, the National Security Council and the Central Intelligence Agency visited the Kurdish territory this year to discuss American options, and had also met with Kurds in Washington and Europe.

At one meeting in Europe this spring, Kurdish officials in Sulaimaniya said, Mr. Barzani and Mr. Talabani, bitter rivals for years, sat down together to meet with American officials. Their main message, the Kurdish officials said, was that Washington should not expect Kurds to subordinate their own safety to American priorities. "Nobody has suffered more from Saddam than the Kurds," one senior official said. "We told the Americans, `This time, the Kurds will put their own interests first, and last.' "

Although the Kurds' fear of again being abandoned by the United States seemed real, the greater fear seemed to be of Mr. Hussein. An official in Erbil acknowledged that the Kurdish leaders, in publicly discouraging American military action, were signaling to the Iraqi leader that the Americans, not the Kurds, were his adversaries. "Saddam is our shadow," the official said. "He's always there, right behind us, and we don't want him to think that we're drawing the Americans in to overthrow him."

Concern among the Kurds seems certain to increase with the failure in Vienna on Friday of the latest talks between the United Nations secretary general, Kofi Annan, and Iraqi officials aimed at resuming United Nations weapons inspections in Iraq. The inspections are to determine whether Baghdad is continuing efforts toward building nuclear, chemical and biological weapons, as Washington has charged, and to destroy any programs that are found.

Many United Nations members, including important American allies, see a resumption of weapons inspections, suspended after Mr. Hussein drove inspectors from Baghdad in 1998, as the only way of forestalling American military action. United Nations and Iraqi officials said talks would continue in Europe in coming months, but Washington viewed the Vienna meeting as a watershed. Iraqi officials placed blame for the talks' failure on an "American plot" to prepare for a military attack.

In an American-led campaign, Kurdish territory would be a crucial platform for a ground assault.

In one plan discussed in Washington, American forces, with Kurdish and other Iraqi opposition fighters, would seek to replicate the war against the Taliban in Afghanistan, using the Kurdish-controlled areas and troops much as the territory and troops of the Afghan Northern Alliance were used.

But the Kurdish leaders, in the interviews, said they would resist any American actions aimed at toppling Mr. Hussein unless Washington gave "guarantees" in advance. They said these would include an undertaking that a future Iraqi government would adopt a democratic political system, with a federal structure that provided for wide-ranging Kurdish autonomy in the north.

In effect, this would require Washington to promise that Kurds would maintain effective control of the area they now rule. But it is far from certain that other Iraqi opposition groups drawing support from the country's Arabs would agree, partly because of the Baghdad's reliance on revenues from the north's oil fields.

The Kurdish leaders spoke with a sharp edge of distrust for the United States, which they said had "betrayed" Iraqi Kurds at crucial moments in the past, most recently during the Iraqi onslaught against the Kurdish uprising in 1991. Mr. Barzani and other leaders also referred bitterly to events in 1975, when the United States encouraged Iraqi Kurds to ally themselves with Shah Mohammed Reza Pahlavi of Iran in a territorial dispute with Iraq, only to back a reconciliation between Iran and Iraq that left the Kurds exposed to a military crackdown by Baghdad.

Mr. Barzani coupled this bitterness with a reminder that Washington's hawkishness on Iraq is led by a president whose father, many Iraqi Kurds contend, let them down in 1991.

After American troops liberated Kuwait, then stopped at Iraq's southern border, the first President Bush encouraged Kurds in northern Iraq and Shiite Muslims in the south to "take matters into their own hands." He then withheld American military support when their uprisings drew savage retribution from Baghdad.

When they discuss American plans, the Kurdish leaders reserve their harshest condemnation for any attempt to topple Mr. Hussein by C.I.A.-led covert action, possibly by fomenting a military coup. Reports from Washington have said Mr. Bush this year strengthened a presidential directive authorizing the C.I.A. to mount covert operations inside Iraq with the aim of toppling Mr. Hussein, and authorized American agents to kill him if necessary in self-defense.

But Barham Salih, who heads the government in the eastern half of the Kurdish territory under the authority of Mr. Talabani, said American officials had been told bluntly that the Kurds would oppose any attempt to topple Mr. Hussein by a coup. "We are not interested in exchanging one dictator for another," Mr. Salih said. "We want a democratic, pluralistic, responsible government in Iraq, and that cannot come from a coup."