Abdullah Ocalan, the jailed Kurdish rebel leader, has issued a long-awaited ceasefire declaration that would be a major step towards ending a 30-year conflict that has cost around 40,000 lives in Turkey.
The ceasefire, announced on Thursday and which coincides with the Kurdish New Year, or Newroz, also calls for the withdrawal of PKK likely to bases in northern Iraq.
Recep Tayyip Erdogan, the Turkish prime minister, said the ceasefire call was a "positive development".
"There are groups that are fed by terror in our country. This process will ruin their game." he said, speaking during a visit to the Netherlands.
In Ocalan's letter, read out by members of parliament, Pervin Buldan, in Kurdish, and Sirri Sureyya Onder, in Turkish, the PKK leader said: "Let guns be silenced and poltics dominate.
"The stage has been reached where our armed forces should withdraw beyond the borders ... It's not the end. It's the start of a new era."
The statement was read out to a sea of red-yellow-green Kurdish flags, in the Kurdish-majority city of Diyarbakir, where hundreds of thousands gathered for celebrations.
Erdogan expressed his disappointment because there were no Turkish flags at the Newroz celebrations in Diyarbakir.
"This is a provocative approach by the circles who wants to influence the process in a negative way," he said.
Ocalan's ceasefire is likely to be in return for wider constitutional recognition and language rights for Turkey's up to 15 million Kurds.
The peace plan is the result of written consultations between Ocalan, pro-Kurdish legislators and PKK bodies in Europe and northern Iraq, under the close monitoring of Turkish agents.
Kurdish legislators say Ocalan might ask for commissions to be established to properly monitor the ceasefire, and call for safe passage for fighters wishing to leave Turkey.
Erdogan and Ocalan both appear to have staked their political futures on the renewed push to end the conflict.
Al Jazeera's Zeina Khodr, reporting from Diyarbakir, said Erdogan had made no secret that he was eyeing the presidency.
"He will need to amend the constitution and would like to increase the powers of the president. He can not do that without the support of the Kurdish party, the BDP."
Erdogan said he was putting his faith in the peace process "even if it costs me my political career", in the face of accusations that Ankara was making concessions to Ocalan.
Ocalan, known as "Apo," has said he wants peace for the greater good of his people.
"Consider Apo dead if this process fails. I am simply out," the burly 64-year-old was quoted as saying in a rare prison meeting with Kurdish legislators last month.
Hard road ahead
If a ceasefire holds, the path to disarmament, and the reintegration of PKK fighters, will still be long and vulnerable to sabotage.
The fate of Ocalan also remains uncertain, but any move to release him would be strongly opposed by critics who see any settlement as threatening Turkish unity.
The prospect of talks with the PKK has outraged many Turks who revile Ocalan and hold him personally responsible for the bloodshed.