"We have decided to extend our truce announced on April 13 until July 15 in the light of the positive conditions which have appeared," the outlawed Kurdistan Workers' Party (PKK) said in a statement carried by its mouthpiece, the Firat news agency.

The truce was designed to help bring about a "democratic resolution to the Kurdish question", the statement added.

The current truce had been due to expire on June 1.

The Turkish authorities have never formally recognised previous unilateral truces declared by the rebels and have pledged to push on with their pursuit of the outlawed movement.

The PKK leadership also indicated in the statement that they would be prepared to extend the truce until September as long as they did not come under attack from the Turkish army.

The announcement comes after recent comments from Turkish President Abdullah Gul who said "an historic opportunity" was opening up to resolve the conflict, without giving further details.

The PKK -- regarded as a terrorist group by Turkey, the European Union and United States -- took up arms for self-rule in Turkey's Kurdish-majority southeast in 1984, sparking a conflict that has claimed about 44,000 lives.

Eager to boost its bid to join the European Union, Ankara has in recent years granted the Kurds a series of cultural freedoms, but failed to draw up a specific strategy to convince the PKK to end its armed struggle.

The government rules out dialogue with the PKK and has rejected calls by Kurdish activists to consider a general amnesty for the rebels.

Speaking in April, Turkey's army chief Ilker Basbug said that the PKK was on the ropes, beset by problems in its command structure and low morale.