"Our people have every right to defend themselves and to retaliate. This right is sacred and our people will do what is required," the PKK said in a statement carried by the Firat news agency, considered to be a rebel mouthpiece.

The PKK said five of its militants and two civilians were killed in Sunday's raids on positions along the Turkish border and in the Qandil mountains to the east along the Iraqi-Iranian frontier, where the PKK is known to have bases.

The Turkish army strongly denied its warplanes targeted civilians. It has not yet given a casualty figure.

Chief of staff General Yasar Buyukanit said the United States gave tacit consent for the operation by providing "intelligence" and opening Iraqi airspace.

The PKK said its positions also came under artillery fire from Iran following the Turkish air raid and put the "primary" blame on the United States.

"Even though this attack ... was conducted by the Turkish and Iranian armies, it is obvious that the United States is primarily responsible for providing this opportunity," the statement, published on Firat's website, said.

The PKK, listed as a terrorist group by Ankara and much of the international community, enjoys refuge in the rugged mountains of Kurdish-populated northern Iraq and uses bases there as a springboard for attacks in southeast Turkey.

It has waged a bloody campaign for Kurdish self-rule since 1984 in a conflict that has claimed more than 37,000 lives.

Iran, which has its own restive Kurdish minority, also complains that Kurdish rebels from PJAK, a PKK-linked group, take refuge in northern Iraq.