Jailed Kurdish leader Abdullah Ocalan called Thursday for his militant group to lay down its arms and disband as part of a new attempt to end a four-decade conflict that has claimed tens of thousands of lives, the Associated Press reported.

In a message from a prison on an island near Istanbul on Thursday, Ocalan said the Kurdistan Workers' Party (PKK) should hold a congress and decide to disband.

“Call your congress and make a decision. All groups should lay down their arms and the PKK should dissolve itself,” Ocalan said, according to a message relayed by pro-Kurdish party politicians who visited Ocalan earlier in the day.

Ocalan's landmark statement was part of a new effort to achieve peace between the Kurdish group and Turkey, which was initiated by President Recep Tayyip Erdogan's coalition partner Devlet Bahceli in October. The far-right politician said Ocalan could be released on parole if his party renounces violence and disintegrates.

Ocalan, 75, has been imprisoned on Imrali Island near Istanbul since 1999 on treason charges. Despite his imprisonment, he continues to exert considerable influence over the PKK. The group's leadership is expected to heed any call from Ocalan, although some factions within the group may resist, analysts say.

The peace effort comes at a time when Erdogan may need the support of the DEM party in parliament to pass a new constitution that would allow him to stay in power.