For years, Muslim led the Democratic Union Party (PYD), Syria's most powerful Kurdish party.

He was highly respected in the Kurdish community, and played a key role in shaping its politics in Syria.

The PYD in a statement mourned Muslim "who devoted his life to serving his people's cause and defending their legitimate rights".

It said that Muslim died in a hospital in Erbil, the capital of Iraq's autonomous Kurdistan region, "after a long battle with illness".

An AFP journalist in Erbil reported that friends and party members gathered in front of the hospital to bid Muslim farewell.

His body will be returned to Syria on Thursday for burial, a party official said.

Born in 1951, Muslim hailed from the city of Kobane, once symbolic of Kurdish fighters' victory against Islamic State group jihadists in Syria.

Salih helped establish the semi-autonomous Kurdish region in northeast Syria in 2012 during the civil war, but Kurds have recently had to make concessions to Syria's new Islamist authorities.

Ankara considers Muslim's PYD party and its armed wing, the People's Protection Units (YPG), to be affiliates of the Kurdistan Workers' Party, which has waged a decades-long insurgency against the Turkish state.

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