"We hope that this is just a short-term incursion," spokeswoman Dana Perino told reporters, after Turkish troops pressed an offensive in northern Iraq and fighter jets pounded Kurdish rebel positions on Sunday and overnight.

The raids struck near the Turkish border in and around Hakurk, a prominent stronghold of the Kurdistan Workers' Party (PKK), which for decades has waged a bloody struggle in southeastern Turkey for an independent Kurdish homeland.

"We understand that ... Turkey wants to protect their citizens," Perino said.

"We are in communication and dialogue with them to make sure that this is handled in a way that is narrow, narrowly targeted, to hit the PKK and to limit and hopefully cause no civilian casualties."