Ocalan, leader of the militant organization Kurdistan Workers' Party, in March called on his fighters to leave Turkey as part of a peace initiative brokered with the government. PKK fighters were slow to move out of the country and Turkish Prime Minister Recep Tayyip Erdogan last week said militants weren't serious about peace.
"The promises given concerning withdrawal from Turkey have not been kept," he was quoted as saying Friday by Turkish newspaper Today's Zaman.
Kurdish leaders said they were frustrated by the lack of security guarantees from the government. Selahattin Demirtas, leader of the pro-Kurdish Peace and Democracy Party, said moving Ocalan to a larger prison cell would help facilitate the peace process.
"A change in Ocalan's prison conditions will affect the course of the process," he was quoted Monday as saying. "Ocalan should be allowed to meet with intellectuals, writers, media members and wise people [to discuss the issue]."
Thousands of people on both sides were killed during the 30-year conflict between the PKK and the Turkish government. The PKK is pressing for more Kurdish rights.