Turkey will push U.S. Secretary of State Condoleezza Rice this week to follow through on promises to help eradicate Kurdish rebels in northern Iraq but experts say the top U.S. diplomat's hands are tied.

Rice arrives in Ankara on Friday for talks with Turkey's leaders, before going to Istanbul for a meeting of Iraq's neighbors and major powers that is also expected to be dominated by tensions between Iraq and Turkey.

"I can't imagine what she is going to be able to do in terms of pulling a rabbit out of the hat that would enable her to leave claiming that some progress had been made," said Mark Parris, a former U.S. ambassador to Turkey.

Turkey has threatened a military incursion into northern Iraq, from where Kurdish rebels have launched attacks, but has so far heeded Washington's call for restraint.

Washington fears an incursion by Turkey -- a NATO ally and key conduit for supplies to U.S. troops in Iraq and Afghanistan -- would further destabilize an already volatile region.

Rice has promised unspecified "concrete action" and is prodding Iraq's government, particularly the Kurdish regional authorities in northern Iraq, to curb the Kurdistan Workers Party, or PKK, by closing its bases and arresting leaders.

"We are looking to the Iraqi government to act, to act to prevent terrorist attacks, and ultimately to act to dismantle that terror group that's operating on their territory," State Department spokesman Sean McCormack said.

But while Rice has promised U.S. action and urged the Iraqis to do more, defense officials have made clear there is no appetite for U.S. military action against the PKK.

Major-Gen. Benjamin Mixon, in charge of U.S. forces in the north of Iraq, said when asked last week what he planned to do to curb the activities of the PKK: "Absolutely nothing."

Turkey expert Sam Brannen, international security fellow at the Center for Strategic and International Studies, said Mixon's comments went over "like a lead balloon" in Turkey.

"I think she (Rice) is going in really hamstrung in what she can achieve on this trip," said Brannen.

The view in Turkey is that the United States is not prepared to act against the PKK for fear of alienating the Kurdistan Regional Government (KRG) in Iraq, experts say.

TWO GIRLFRIENDS

"They are frustrated that the U.S. has not done more. I don't see anything changing," said Zeyno Baran of the Hudson Institute.

She likened it to the United States having two girlfriends -- Iraq and Turkey -- and Ankara pushing Washington to choose between them.

Rice's visit coincides with increasingly anti-U.S. sentiment in Turkey and residual anger after a resolution passed by a U.S. congressional committee this month that called the 1915 massacre of Armenians by Ottoman Turks a genocide.

Turkey's Prime Minister Tayyip Erdogan is set to meet President George W. Bush in Washington next week and Rice's sessions in Turkey are aimed at smoothing out problems before then.

A recent poll by the Pew Research Center put the U.S. favorability rating in Turkey at 9 percent versus 52 percent in 2000. Turks now see the United States as the single biggest threat to their nation's security.

"The fact is that Secretary Rice is going into the jaws of a real credibility problem and is up against some real narrow parameters in terms of what she can do to overcome that credibility problem," said Parris, now with the Brookings Institution.

Several experts suggest Rice should start laying the foundation for dialogue between Iraq and Turkey over the PKK.

"The best interlocutors are the Iraqi Kurds but the Turks are so petrified by the possibility that the Iraqi Kurds will go independent and then act as a beacon for the Turkish Kurds that they don't even recognize the KRG," said former State Department official Henri Barkey.

But a senior State Department official said Rice was unlikely to offer herself as a go-between.

"She will consult on our latest thinking and planning and next steps to advance that cooperation which has to be between Iraq and Turkey," he said, adding that "next steps" involved classified information and he could not be more specific.

Barkey, who is now at Lehigh University in Pennsylvania, said the United States had poorly handled the problem with the PKK and Rice's best shot of success was cold weather, when rebels usually hunkered down and skirmishes declined.

"Rice should be praying for snow," said Barkey.

Afghanistan Iraq