LONDON (Reuters)-The leader of the Kurdistan Workers' Party (PKK) warned Turkey on Tuesday it will end its cease-fire if the government steps up military operations against the Kurdish liberation organization.

In an interview with Britain's Independent newspaper, Murat Karayilan was quoted as saying time was running out for the Turkish authorities to pursue a peaceful solution.

"We will wait another 15 days," Karayilan told the newspaper from his hideout in northern Iraq, where the group is mainly based.

"If something positive develops, we will extend the unilateral cease-fire. If there are no concrete steps, we will evaluate developments and do what we have to do to defend ourselves."

More than 40,000 people, mostly Kurds, have been killed since the PKK took up arms in 1984 to defend against Turkish military raids steming from their desire for liberation. The PKK says they now want greater rights and autonomy for Turkey's estimated 15 million Kurds.

On August 13 the PKK declared a one-month, unilateral truce that it then extended for an indefinite period on Sept. 30.

Despite the cease-fire, there have been fatal clashes between PKK rebels and Turkish soldiers in southeast Turkey.

Karayilan told the paper the Turkish government has used the cease-fire to "surround and destroy" the group.

"If attacks are carried out, all the Kurdish people will be part of the defense strategy," Karayilan said.

"The issue is not between the Turkish state and the PKK. It is between the Turkish state and the Kurdish people."

The United States and the European Union, like Turkey, classify the PKK as a terrorist organization.