Secretary of State Condoleezza Rice assured Turkish officials Friday that Kurdish rebels based in northern Iraq were a "common threat" and that the United States would help Ankara in its fight against them.

Speaking after meeting with Prime Minister Recep Tayyip Erdogan and Foreign Minister Ali Babacan, Rice said she had emphasized that the United States is "committed to redoubling its efforts" to help Turkey in its struggle against the rebel fighters.

"We consider this a common threat, not just to the interests of Turkey but to the interests of the United States as well," she said at a joint news conference with Babacan. "This is going to take persistence and it's going to take commitment — this is a very difficult problem."

En route here, Rice told reporters in her traveling party that the United States, Turkey and Iraq will counter any attacks on Turkey by the rebels.

She didn't specify just what that meant but did warn against doing anything that might worsen the volatile situation on the Turkish-Iraqi border.

Washington worries that a cross-border incursion would bring instability to what has been the calmest part of Iraq, and could set a precedent for other countries, like Iran, who also have conflicts with Kurdish rebels.

But Ankara has been resolute in saying that, unless it hears concrete measures the United States will take against the rebel Kurdistan Workers' Party, or PKK, it will launch an attack.

"We have great expectations from the United States, we are at the point where words have been exhausted and where there is need for action," Babacan said.

Rice said the U.S. was looking at enhancing its intelligence and information sharing with Turkey and that she had begun talking with the Turkish leaders about longer term solutions.

"The United States is committed to redoubling its efforts, because we need a comprehensive approach to this problem..." she said. "No one should doubt the United States in this situation."