Fighting between Kurdish rebels and Turkey's army and air force in southeastern Turkey and northern Iraq killed 15 soldiers and at least 23 insurgents, the military said Saturday, in the deadliest battle between them in eight months.

Prime Minister Recep Tayyip Erdogan said 20 soldiers also were wounded in the fighting, and the battle prompted him to cut short an official visit to Turkmenistan and return home Saturday.

President Abdullah Gul also canceled an official visit to France, scheduled for Sunday. "Whatever the cost, the fight will go on full force," Gul told reporters before meeting with Gen. Ilker Basbug, the chief of the military.

Friday's fighting involved a rebel attack on soldiers near a military outpost in southeastern Turkey, and Turkish warplanes, helicopters and artillery units pounding insurgent positions in northern Iraq, said Brig. Gen. Metin Gurak, a military spokesman.

Gurak said the Turkish forces were reacting to Kurdish rebel movements they had detected in northern Iraq and the rebel attack near the outpost in Aktutun, Turkey, about six miles north of the Iraqi border.

Gurak's statement said most of the 15 Turkish fatalities occurred near the outpost and were the result of heavy rebel fire from northern Iraq. He did not identify the weapons used by the insurgents, but the pro-Kurdish Firat news agency's Web site quoted Kurdish rebels as saying they used rocket launchers and assault rifles in the attack.

Turkish forces killed at least 23 Kurdish rebels, but more may have died during the artillery and air force attacks in northern Iraq, Gurak said.

He did not say whether soldiers crossed the border into Iraq during the fighting.

In addition to the 15 soldiers killed, two were missing, Gurak said. The Kurdistan Workers' Party, or PKK, insurgents have kidnapped Turkish soldiers in the past during similar attacks.

Iraq's government, the European Union and the U.S. Embassy in Ankara issued statements Saturday condemning the rebels and supporting Turkey.

"We mourn with the citizens of Turkey and extend our condolences to the families of the soldiers who lost their lives," the embassy said. "President Georgia W. Bush has labeled the PKK a common enemy of the United States, Turkey and Iraq, and we reiterate our long-standing call for the PKK to lay down its arms and cease its violence once and for all."

Friday's fighting was the deadliest battle between Kurdish rebels and Turkish forces since February, when Turkey staged a weeklong ground offensive against guerrillas based in northern Iraq and claimed to have killed hundreds of them. Friday's rebel attack also came two weeks after Gen. Basbug said the insurgents were "withering" under the military's operations.

Next week, Turkey's Parliament is scheduled to vote on a proposal to extend for another year a mandate giving its military authorization for cross-border operations against Kurdish rebel bases in northern Iraq. The current authority which expires on Oct. 17.

The military has said its cross-border offensives have destroyed several rebel hideouts, but the PKK insurgents have denied that. The rebels, based in predominantly Kurdish southeastern Turkey and northern Iraq, have been fighting for autonomy since 1984, alleging a history of discrimination and human rights abuses against the Kurds.