Syria rebel chief killing doesn't serve peace: Saudi

The killing of a Syrian rebel chief in an air raid last week does not serve the peace process in the war-ravaged country, Saudi Foreign Minister Adel al-Jubeir said on Tuesday.

Zahran Alloush, the head of the Saudi-backed Jaish al-Islam, the foremost rebel group in Damascus province, was killed on Friday in a strike claimed by Syria's government.

"Attempts to assassinate leaderships fighting Daesh do not serve the peace process and [efforts] to achieve a political solution in Syria," Jubeir said, using the Arabic acronym for the Islamic State (IS) group.

Although Syria's army command reportedly said it conducted the operation that killed Alloush, rebel sources have said that the Russians conducted the strike, a claim that Russia's state-run media has denied.

"I don't know what the Russians have in mind," Jubeir told reporters, in reference to the killing.

The minister was speaking at a joint news conference in Riyadh with his Turkish counterpart, Mevlut Cavusoglu. Turkish President Recep Tayyip Erdogan was also in Saudi Arabia on Tuesday and met with King Salman.

Jaish al-Islam has fought off both Syrian government forces and IS militants in its Eastern Ghouta bastion, east of Damascus.

It has also come under criticism from human rights groups for rights abuses, including executing alleged members of IS in a video mimicking IS's own gruesome productions.

Earlier this month in an unprecedented meeting of Syrian opposition groups in Riyadh, the group agreed to eventual peace talks with the Syrian government, support that analysts say lent the move for opposition-government talks much needed credibility.

Alloush's killing could therefore thwart potential peace talks between the government and the opposition, which the UN announced could begin next month, analysts said.

Saudi Arabia is a key backer of Syrian rebel groups battling President Bashar al-Assad's government, and Jubeir reiterated previous demands that Assad be removed from power.

Cavusoglu echoed his counterpart's calls: "Our views on Syria match. We cannot reach a solution with Assad's presence."

Separately, he said the majority of Russia's air strikes on Syria are not targeting IS.

"If you are really willing to confront IS, then let us agree and eliminate it," Cavusoglu said, addressing Russia, which he accused of having "goals other than eliminating IS".

A bitter diplomatic row flared between Moscow and Ankara, which back different sides in Syria's war, after Turkey shot down a Russian fighter jet on its border with Syria at the end of November.