Factbox-What is the PKK, the militant group urged by its leader to disband and make peace with Turkey?

ISTANBUL (Reuters) - The jailed founder of the Kurdistan Workers Party (PKK), Abdullah Ocalan, appealed on Thursday to his militant group to disarm and to dissolve itself.

His call, if heeded by the PKK fighters, opens the door to ending a conflict that has ravaged southeastern Turkey for four decades and will also have significant implications for the wider region, especially neighbouring Syria and Iraq. 

Here are details about the PKK:  

WHAT IS THE PKK?

The PKK is a militant group founded by Ocalan in southeast Turkey in 1978 with an ideology based on Marxist-Leninist ideas.

WHAT DOES THE GROUP WANT?

The PKK launched its insurgency against Turkey in 1984 with the aim of creating an independent Kurdish state. It later moderated its goals to seeking greater Kurdish rights and limited autonomy in southeast Turkey.

More than 40,000 people have been killed in the conflict, most of them militants. Much of the fighting was focused in rural areas of mainly Kurdish southeast Turkey, but the group also conducted attacks in urban areas including Ankara and Istanbul. 

The PKK is listed as a terrorist organisation by Ankara, the United States, the European Union and some other countries.

WHAT IS THE GROUP'S HISTORY?

The PKK operated in Syria until 1998 when Ocalan had to flee amid growing Turkish pressure. He was captured by Turkish special forces several months later in Kenya and sentenced to death by a Turkish court in 1999. The sentence was commuted to life imprisonment in October 2002 after Turkey abolished the death penalty and he is still imprisoned on an island near Istanbul. Fighting dwindled after Ocalan's capture, which led to the withdrawal of rebel fighters from Turkey.

After a flare-up in violence, Turkey and the PKK became involved in peace talks from late 2012. That process collapsed in July 2015, unleashing the bloodiest period of the conflict and resulting in extensive destruction in some urban areas of southeast Turkey.

In October, Devlet Bahceli, the Nationalist Movement Party (MHP) leader and President Tayyip Erdogan's political ally, shocked Ankara when he suggested Ocalan could be released if he announced an end to his group's insurgency. Erdogan's ruling AKP has backed the proposal and leaders of the opposition pro-Kurdish DEM party, which seeks greater Kurdish rights and autonomy, has held talks with Ocalan at his prison.  

WHERE IS THE CONFLICT FOCUSED NOW?

In recent years the conflict has shifted to neighbouring northern Iraq where the PKK has mountain bases and Turkey has dozens of outposts. Ankara has launched operations against the militants there, including air strikes with warplanes and combat drones, which Baghdad has said violates its sovereignty. Yet Iraq and Turkey had agreed to boost anti-PKK cooperation, and Baghdad labelled it a banned organisation for the first time.

Turkey also targets the YPG militia in Syria, regarding it as a PKK affiliate, and has conducted cross-border operations alongside allied Syrian forces to push it back from its border. However the YPG spearheads the SDF, the primary ally of the U.S.-led coalition against Islamic State. Washington's support for the SDF has been a source of U.S.-Turkey tension for years.

The ouster in December of former Syrian President Bashar Al-Assad - whom Ankara long opposed, backing Syrian rebels - bolstered Turkey's position and influence there. It called for the YPG to be disbanded and its leaders expelled from Syria, and threatened a Turkish military operation to "crush" the group if its demands were not met. Turkish, U.S., Syrian and Kurdish officials have sought an agreement on the future of the Syrian Kurdish fighters. 

(Reporting by Tuvan Gumrukcu; Editing by Janet Lawrence and Gareth Jones)