Turkey reacted with alarm and frustration to the sudden takeover of the Iraqi oil city of Kirkuk by Kurdish militias today, but the government urged caution and said it would give the United States time to persuade the Kurds to withdraw before ordering Turkish troops to invade and expel them.

Turkey has repeatedly warned it would respond with force to any move into Kirkuk by the Iraqi Kurds, because it believes they might use the city's oil wealth to establish an independent Kurdish state. That, in turn, could revive a violent separatist movement among the large Kurdish population in southeastern Turkey, which borders northern Iraq.

In an interview on national television, Foreign Minister Abdullah Gul said Turkey was prepared to do "whatever is necessary" to protect its security. But he played down the possibility of a Turkish invasion, and said Turkey was counting on U.S. troops to take control of Kirkuk and "remove" the Kurdish fighters. He said Secretary of State Colin L. Powell promised in a phone call today that the U.S. military would do so.

"We are monitoring the situation closely. [Powell] said they were going to remove all those who entered the city. . . . He said they would absolutely not allow a fait accompli," Gul said. "I hope this mistake will be corrected immediately."

Gul said Powell also agreed to allow Turkey to send military observers to Kirkuk to ensure the Kurds leave, adding that they would be stationed "everywhere." U.S. officials said the soldiers would accompany American troops, but declined to provide details about the Turkish deployment, which might upset Iraqi Kurds who have objected to any Turkish incursion into their territory.

Gul blamed the takeover of Kirkuk on pesh merga fighters from the Patriotic Union of Kurdistan (PUK), one of the two main Kurdish parties in northern Iraq. He said the other party, the Kurdistan Democratic Party, contacted Ankara, condemned the capture of Kirkuk and agreed to help the Turkish army drive the other Kurdish group out of the city if necessary.

But late tonight, speaking on the CNN-Turk television station, PUK leader Jalal Talabani announced he had ordered his forces to leave Kirkuk by Friday morning.

"They will leave tomorrow, I promise you. . . . When the American troops come, the pesh merga will leave," he said. "From tomorrow morning on, no one will see any pesh merga. . . . There is no crisis. The crisis is over. There will never be a crisis between our Turkish brothers and us."

He said his militias entered the city to prevent looting until U.S. forces could arrive. "You know, the people hated the regime so much. Thousands were celebrating. Therefore, it wasn't possible for us to control it," Talabani said. "There will be more discipline and order tomorrow morning."

Earlier in the day, Gul sought to reassure the Turkish public, saying only a small number of Kurdish fighters had entered Kirkuk and insisting "there is no need to be worried." But even as he spoke, Turkish television showed images of thousands of armed Kurds celebrating in Kirkuk and broadcast reports of Kurds looting the homes and businesses of the city's Turkmen residents, whom the Turks consider their ethnic cousins and had vowed to protect.

Turkish journalists in Kirkuk said the Kurds destroyed land records at the courthouse, which would make it easier for them to expel Turkmens from the city, and they broadcast interviews with tearful Turkmens who pleaded for the Turkish army to intervene. "The Kurds are coming here, taking away our cars, our belongings. We're not secure," said one Turkmen resident.

Sanan Ahmet Aga, chief of the Iraqi Turkmen Front, the Iraqi Turkmen group supported by Turkey, urged the Turkish army to enter Kirkuk as observers and "save us from this pressure, from this fear."

"If the U.S. makes a promise, it has to keep it. In this region, many promises are made, but they aren't kept," he said.

Across the political spectrum in Turkey, there was a sense of deep frustration about the Kurdish capture of Kirkuk, with many complaining the United States had let Turks down, and perhaps had deliberately misled them. Powell and other U.S. officials had repeatedly promised to keep the Kurds out of the city, but the Turks always had doubts, pressing the United States on how it intended to seize the city when it only had 3,000 troops in northern Iraq, compared with the estimated 70,000 Kurdish fighters there.

To many, those doubts were justified today. "What is happening in Kirkuk is unbelievable," said Mehmet Dulger, chairman of the parliament's foreign affairs committee. "It's a very bad scene."

Mehmet Agar, leader of the opposition True Path Party, fumed at the Kurds, saying they would be "made to eat those land records. . . . Nobody should mix up the Turkish army with the Iraqi Republican Guard."

"Obviously, people are unhappy," said one senior Turkish official, who asked not to be identified. "We said we didn't want this to happen. We said it would be destabilizing. We warned our allies."

But the official said Turkey had little choice but to put its trust in the United States again. A unilateral Turkish move into northern Iraq would cause serious damage to relations with Washington, which has kept Turkey's fragile economy from collapsing by backing huge IMF loans. It would also hurt Turkey's standing within NATO and its chances of entering the European Union; leaders of both organizations have warned Turkey to stay out of northern Iraq.

"Turkey has to believe in the United States," said Metehan Demir, a military affairs writer for Hurriyet, Turkey's largest newspaper. "It has no other option to avoid war."

Emin Sirin, vice chairman of the foreign relations committee, said Turkey was counting on the United States to follow through this time.

"We're going to give them the necessary time, a couple of days or maybe a week, and see if they can keep their promises and convince the Kurds to leave," Sirin said. "I hope the U.S. will convince them to leave. Otherwise, they'll be forced to leave. Turkey will force them out."

Turkish soldiers and tanks are stationed about 30 miles from Iraq. Foreign Minister Abdullah Gul said Turkey was counting on U.S. troops to "remove" Kurdish fighters from Kirkuk.