U.S. President George W. Bush promised Turkey's president Monday that the United States will join Ankara's effort to fight against Kurdistan Workers' Party (PKK) operating at Turkey-Iraq border area, the White House said.

In a telephone call with Turkish President Abdullah Gul Gul, Bush "expressed his deep concern about the recent attacks by PKK terrorists against Turkish soldiers and civilians," U.S. National Security Council spokesman Gordon Johndroe told reporters. 
"The president reaffirmed our commitment to work with Turkey and Iraq to combat PKK terrorists operating out of northern Iraq," Johndroe said.

Prior to Bush's telephone talk with Gul, U.S. Secretary of State Condoleezza Rice called Turkish Prime Minister Recep Tayyip Erdogan and Massoud Barzani, leader of Iraq's Kurdish region, on Sunday, urging Turkey to show restraint, and Iraq to take action against the outlawed PKK, the State Department spokesman Sean McCormack said Monday.

Stressing that the United States regards the PKK as a terrorist organization, McCormack said the best way to solve the issue "is for the Turks and the Iraqis to work together to mitigate it and eliminate it."

"We are going to do everything we can to encourage Turkey and Iraq to work together to address what is a common threat," the spokesman said.

Turkey has vowed to take all necessary measures against the Kurdish rebels, including a possible incursion into northern Iraq after dozens of Turkish soldiers were recently killed by PKK militants.

The PKK, listed as a terrorist organization by Turkey, the United States and the European Union, launched an armed campaign for an ethnic homeland in the mainly Kurdish southeastern Turkey in 1984, sparking decades of strife that has claimed more than 30,000 lives.

Editor: Yan