A senior U.S. military official said Wednesday he knew of no Turkish airstrikes or cross-border incursions into northern Iraq despite reports of such attacks on Kurdish rebels along the border. The semi-official Anatolia news agency said Turkish warplanes bombed several Kurdish Workers Party (PKK) positions in provinces along the border with Iraq, and that helicopter gunships also took part in operations. “I don't know that there have been any Turkish airstrikes or cross-border operations into Iraq,” said Major General Richard Sherlock. A Pentagon official said on condition of anonymity that there had been no reports in U.S. military channels of Turkish airstrikes on either side of the border. Separately, a senior U.S. defense official told reporters on condition of anonymity that there was increasing sympathy in Washington for Turkey's insistence that actions be taken against the PKK. “I don't want to get into too much detail. But there are logistics lines, there are things we've done to curtail movement of the PKK,” the official said. “There are a variety of things that might be done to make it, if not impossible, much more difficult for the PKK to operate across the border, which would also be visible to the government of Turkey.” Washington is pressing for a diplomatic solution to the crisis, but the senior official acknowledged that the Turks are under domestic political pressure and may be forced to act. “I would say within the senior reaches of the U.S. government there is increasing sympathy for the Turkish position that something has to be done,” the official said. The official said it was the responsibility of both the Iraqi government and the Kurdish regional government to take measures to stabilize the situation. “I don't think we're going to be prescriptive about who does what, but I think we expect some tangible, concrete things to happen,” the official said.