DIYARBAKIR, Turkey — Imprisoned Kurdish rebel leader Abdullah Ocalan on Saturday renewed a call for his fighters to end their armed struggle against Turkey, part of efforts toward a peaceful resolution of a decades-long insurgency that has killed tens of thousands of people.

In a message read to Kurds celebrating a spring festival, Ocalan said the Kurdistan Workers' Party, or PKK, should convene a congress to decide to abandon arms and seek a democratic solution. Ocalan, however, also suggested that the Turkish government should take democratic steps outlined in a vague 10-point declaration that both sides have agreed on. He called for the establishment of committees to oversee the peace process and help the sides confront their violent past.

"As the principles of the declaration are agreed upon, I see it as essential and historic that the PKK holds a congress to ... bring an end the roughly 40-year armed struggle against the Republic of Turkey," Ocalan said.

His message — read out in Kurdish and Turkish by pro-Kurdish legislators in the mainly Kurdish city of Diyarbakir — received a rapturous response from hundreds of thousands in the crowd.

"A new era is set to begin with this congress," Ocalan said. "In this new era, within the Republic of Turkey, we'll enter a phase where we will live in peace, as sisters and brothers, with a democratic identity and as a democratic society."

A heavy downpour stopped and the sun came out as the message was read. Many in the crowd chanted "Ocalan!", carried his posters and wore clothes emblazoned with his image.

Ocalan made a similar call earlier this month. The PKK responded saying that it would convene a congress only if the Turkish government took steps, including establishing independent observers to monitor the peace process.

There was no immediate PKK response to Ocalan's latest message.

Erdogan has recently criticized government steps to form a committee of observers.

On Saturday, he said he hoped that with Ocalan's message, mothers would no longer "shed tears" and that it would constitute a "milestone for peace and solidarity."

Turkey began talking with Ocalan's group in 2012 in a bid to end one the world's longest, bloodiest conflicts. Despite his 14-year incarceration in a prison island off Istanbul, Ocalan still wields great power over his rebel group.

The PKK — considered a terror organization by Turkey and its Western allies — has been fighting for autonomy and greater rights for Kurds who make up an estimated 20 percent of Turkey's population of 76 million. The group has frequently launched attacks on Turkey from bases in northern Iraq.

Ocalan announced a historic cease-fire to end hostilities during the spring festival, called Newroz, in 2013, and also appealed to his fighters to retreat from Turkey. Later, however, his group halted the withdrawal of fighters from Turkish territory into bases in northern Iraq, saying Turkey had not kept its promises.

Across the border in Syria, a twin bombing attack Friday targeting Kurds celebrating the Newroz holiday, killed at least 20 people and wounded more than 70. It was believed to have been carried out by Islamic State extremists.

Kurdish fighters have been battling the Islamic State group for months, leaving hundreds dead. The fighters of the main Kurdish militia, known as the People's Protection Units, or YPG, have evicted IS fighters from the northern Syrian town of Kobani and dozens of nearby villages with the help of airstrikes from the U.S.-led coalition.

Ocalan in his message saluted the YPG fighters and called the IS an organization that "pushed the boundaries of the meaning of barbarism."

Fraser reported from Ankara, Turkey.