The PKK, or Kurdistan Workers' Party, in May declared an end to its armed conflict and was expected to hold a series of ceremonies to destroy its weapons.

But Mustafa Karasu, one of the group's founders and top leaders, told a Kurdish-linked television station that "a group at the heart of the state is seeking to sabotage the process".

"We are ready, but it is the (Turkish) government that has not taken the needed steps," he said.

Karasu cited the lack of improvement in the prison conditions of the PKK's founder Abdullah Ocalan, who has been held at the Imrali island jail since 1999.

It was Ocalan, now 76, who in February called on the PKK to lay down its weapons after decades of conflict with the Turkish state that has left thousands dead.

"Some friends have gone to Imrali, but it's not enough. The isolation has lasted for 26 years," despite some adjustments, Karasu said.

Karasu did not confirm if any disarmament ceremonies were planned.