Six combat planes targeted Kurdistan Workers' Party (PKK) bases in Zap-Khakurk in Iraq's autonomous Kurdish zone, it said, citing the Internet site of Iraqi President Jalal Talabani's Patriotic Union of Kurdistan (PUK).

The Turkish military did not immediately comment on the action.

But a PKK spokesman in northern Iraq, Ahmad Denis, denied the planes had carried out bombing runs. "The Turkish military planes only overflew the zone at low altitude without dropping bombs," he told AFP.

He said the operation lasted one hour.

In a flareup of fighting, a rocket assault on May 31 claimed by the PKK on a naval base in southern Turkey killed six soldiers and wounded seven in one of the deadliest attacks in months.

The PKK, listed as a terrorist group by Turkey and much of the international community, took up arms in 1984 for self rule in Turkey's Kurdish-majority southeast, sparking a conflict that has claimed some 45,000 lives.

On June 4, PKK spokesman Ahmed Denis said the rebels had ended a unilateral truce with Turkey -- in place since April 2009 -- "because of Turkey's continuing hostility to the Kurdish people".

But last week the president of the Kurdish autonomous zone in northern Iraq, Massud Barzani, pledged at the end of a landmark visit to Turkey "all efforts" to stop separatist Kurdish violence against the country.

The arrival of spring brings a resurgence of violence in the area as the rebels move out from their mountain hideouts in Turkey and Iraq when the snow melts.

About 20 fighter jets reportedly took part in the last Turkish military air strikes on Kurdish positions on May 20, also in the Zap-Khakurk region.

Nearly 50 targets were hit in day-long missions carried out mainly on the basis of intelligence passed on by the United States, the NTV news channel reported at the time.

The Turkish army has staged a series of air raids against PKK bases in northern Iraq since December 2007, often with the help of US intelligence, and in February 2008 carried out a week-long ground incursion.

Ankara says about 2,000 PKK rebels are holed up in the mountains of northern Iraq, from where they launch attacks on Turkish territory.