Syria's opposition is hoping to persuade the US administration this week to throw its weight behind UN-led peace talks and counter Russia's bid to set up a parallel track, lead negotiator Nasr Hariri said Tuesday (January 9th).

After meeting with UN Secretary-General Antonio Guterres in New York, opposition leaders are heading to Washington on Tuesday for meetings to shore up the Geneva talks, expected to resume January 21st, AFP reported.

"All of us, all of our countries are waiting for an American role" in finding a settlement, Hariri said.

The US is "the most important player in the Syrian fight, the only state that can make a balance with the Russian influence", he said.

The delegation led by Hariri hopes to meet with US national security adviser H.R. McMaster, State Department officials and members of Congress to make their case for US engagement.

The opposition's appeal to the US administration comes as Russia is asking the UN to take part in a peace congress it is hosting along with Iran in Sochi on January 29th and 30th.