Talks to unite Syrian rebels "constructive", says Kerry

Talks being held in a bid to unite Syrian opposition groups had made progress, it was reported on Thursday.

US Secretary of State John Kerry made the comments from the Paris climate summit, when discussing the talks being led by Saudi Arabia this week.

The Arab state has been a big supporter of the rebels for more than four years in their attempts to topple Syrian president Bashar al-Assad. It hosted the rebels this week in one of the most serious attempts seen in the conflict to unite the various factions.

"The meeting in Saudi Arabia appears to be very constructive at this point", said Kerry. "I think everybody is moving in the direction that they want to rapidly get to a political process."

"So we made progress, but we have some tough issues to get over", he added.

Kerry told the assembled press that he had a telephone conversation with Russia's foreign minister Sergei Lavrov, Saudi foreign minister Adel al-Jubeir and Qatar's Khaled al-Attiyah on Wednesday.

Russia and the US, along with European and Middle Eastern countries, agreed in November to a two-year plan leading to elections in Syria, though the blueprint left the fate of Assad entirely unresolved.

A mooted December 18 meeting to advance Syrian peace talks was "not locked in yet", according to Kerry, with stakeholders waiting for the outcome of this week's conference in Saudi Arabia.