The imprisoned leader of a Kurdish guerrilla movement that has waged a bloody insurgency against the Turkish state called Thursday for his group to lay down its arms and dissolve, a pivotal declaration that could echo in neighboring countries and help end 40 years of deadly conflict.
Abdullah Ocalan, the leader of the Kurdistan Workers’ Party, or P.K.K., made his appeal in a written statement that was read aloud during a news conference by members of Turkey’s main pro-Kurdish political party who had just visited him in prison.
He said the group had gained ground at a time when “democratic channels of politics were blocked” but had outlived its life-span and should disband.
“Convene your congress and make a decision,” he said in the statement, read aloud first in Kurdish then in Turkish. “All groups must lay down their arms and the P.K.K. must dissolve itself.” Turkey and the Kurds must now move forward “with the spirit of fraternity,” the statement added, saying democracy was the only path to do so.
The news conference was packed with journalists and Kurdish politicians. Some in the audience applauded and gave a standing ovation when a new image of the rarely photographed Mr. Ocalan appeared on a screen.
The rare message from Mr. Ocalan raised the possibility that a conflict that has killed more than 40,000 people over four decades could finally end.
If the P.K.K. lays down it arms, it would resolve Turkey’s most enduring domestic security threat and mark a significant political achievement for President Recep Tayyip Erdogan.
Many Turks would praise him for ending the conflict and, if followed by further conciliatory steps toward the Kurds, could encourage them to support an effort to change the Constitution to allow him to run for a third presidential term.
The P.K.K.’s disarmament could also shift dynamics elsewhere in the Middle East, given Mr. Ocalan’s profound influence over members of the group in Turkey and Iraq as well as Kurdish militias in Syria and Iran.
But there was little indication of what would happen next.
There has been scant public discussion of who would monitor compliance with Mr. Ocalan’s call, what would happen to fighters who comply with it or what — if anything — the government has offered in exchange for the disarmament.
It also remains unclear what Mr. Ocalan’s call will mean for P.K.K. members in Iraq, and for the U.S.-backed Kurdish-led militia that controls much of northeastern Syria and has ties to the P.K.K. Mazloum Abdi, the leader of the U.S.-backed Syrian Democratic Forces, praised Mr. Ocalan’s call on Thursday but said during an online event that it was “not related to us in Syria.”
The P.K.K. is classified as a terrorist organization by Turkey, the United States and other countries.
Mr. Ocalan’s appeal came after a series of talks that included Turkish officials; Mr. Ocalan himself; and members of Turkey’s main pro-Kurdish party, the People’s Equality and Democracy Party, or D.E.M.
In a speech to members of his political party in January, Mr. Erdogan said the government had offered Mr. Ocalan’s group no concessions. But ending the conflict would benefit Turks and Kurds alike, he said.
The goal of the talks was to get “the terror group to disband itself, to surrender its arms unconditionally,” he said.
But in an interview published last week by the P.K.K.-linked Firat News Agency, a senior member of the group suggested that many issues remained unresolved.
“No one should think that there will be an easy negotiation at the table, signatures will be made and everything will be solved,” said the senior member, Duran Kalkan. “The other side wants to eliminate the P.K.K.”
The Kurdish group has been battling the Turkish state since the early 1980s, attacking police stations and military posts and carrying out bombings that have killed many civilians. It began as a secessionist group that sought to create an independent state for Turkey’s Kurdish minority, but now says it seeks greater rights for Kurds inside Turkey.
For many Turks, Mr. Ocalan is the country’s most despised terrorist. Turkish officials and news outlets often refer to him as “baby killer” or “chief terrorist.” Convicted in 1999 of leading an armed terrorist group, Mr. Ocalan has been in prison for a quarter-century.
Turkey and the P.K.K. have tried over the years to resolve the conflict, most recently through peace talks that started in 2011. But negotiations broke down in 2015, ushering in a deadly new phase.
Last October, a powerful political ally of Mr. Erdogan made a surprising public call to Mr. Ocalan, asking him to tell his fighters to lay down their arms and end the conflict. Doing so, the politician said, could open a pathway for his life sentence in a Turkish prison to be ended.
That led to limited prison visits from relatives and political allies of Mr. Ocalan to explore the possibility of a new peace process.
Regional and domestic dynamics might have prompted the Turkish government to take a new look at its conflict with the P.K.K. Conflicts bubbling up around the Middle East may have motivated Turkey’s leaders to try to ensure stability at home.
Turkey’s military has seriously degraded the P.K.K.’s military capabilities, which may have made the group more open to negotiations.
And the rise of a Turkish-allied rebel group to power in Syria in December has left the Kurdish-led Syrian Democratic Forces in northeastern Syria vulnerable and in danger of having its power eroded.
“Turkey’s space of maneuver expanded significantly,” said Sinem Adar, a Berlin-based, Turkey analyst at the German Institute for International and Security Affairs. “It is a now-or-never moment for Turkey” to weaken the territorial control of the Kurdish militia in Syria, which it considers as a threat to its security, she added.
On Thursday in Diyarbakir, a predominantly Kurdish city in eastern Turkey, Mr. Ocalan’s call for disarmament drew mixed emotions.
Hundreds of people had gathered in the city center to listen to his message, which was broadcast through large loudspeakers dotting the Dagkapi Square.
A few, like Baran Aydin, a 29-year-old Kurd who said he had been imprisoned for seven years for P.K.K.-related charges and had been released only a week ago, said they trusted Mr. Ocalan’s decision making and were hopeful. But more left crying in frustration and confusion when the reading in Kurdish ended.
“I am not sure what I am feeling,’’ said Sakir İlbey, a 58-year-old Kurd. “Peace means being equal to a Turk.”
But “I don’t trust the state,” he added.
Mem Erzen, 24, said he had expected Mr. Ocalan would call for disarmament, but was nevertheless disappointed.
“I have witnessed losses most of my life,” he said. “I understand now it is time for diplomacy,” he added. “But I am sad.”
Murat Bayram contributed reporting.