Syria peace talks: Opposition 'risks US-UK support'
Britain and the US have warned they will rethink support for Syria's main opposition group if it fails to join peace talks, a Syrian source has said.
The official from the Syrian National Coalition told reporters that the UK and the US were adamant the group must go to Geneva for next week's talks.
The coalition will hold a vote on Friday on whether or not to attend.
Syria's opposition remains deeply divided nearly three years after the uprising began.
It is hoped that the talks in Switzerland - known as Geneva II - will provide a breakthrough in ending the bitter civil war.
BBC diplomatic correspondent Bridget Kendall says that, in public, the British government maintains it will not abandon the Syrian National Council.
However, it is clear that persuading the opposition to agree to come face to face with President Bashar al-Assad's government is proving incredibly difficult, she says.
Credibility 'at risk'
"The US and UK are telling us you need to go to Geneva," said the official, who asked not to be named.
"They are making it very clear that they will not continue to support us the way they are doing now and that we will lose credibility with the international community if we do not go."
He said that other foreign backers were not applying the same pressure.
"France is asking us to go but saying that we are with you whatever your decision. That is the same as the Saudi and Turkish stance - [they say] we prefer for you to go to Geneva, but if you do not or it does not work, we will not abandon you."
The official said political support from Washington and London was important to the coalition and its withdrawal would make a difference.
However he also questioned whether such a threat was credible.
He argued that without the moderate opposition the only alternatives left in Syria would be the Assad government or extremists.
"What is the alternative? They have a brutal dictator who used chemical weapons on one side and al-Qaeda on the other, so who will they deal with, if not with us?"
Earlier, the US and Russia said they had discussed the possibility of "localised ceasefires" in Syria ahead of the peace talks.
US Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov said a prisoner exchange was also under consideration.
The two men have been in Paris to discuss arrangements for the Geneva talks, along with Lakhdar Brahimi the UN and Arab League envoy for Syria.
Mr Lavrov and Mr Brahimi also said Iran should take part in the talks.
However, Mr Kerry said to be able to take part, Tehran needed to agree to the Geneva I communique, which calls for a political transition in Syria.
The UN says more than 100,000 people have died since the Syrian uprising began in March 2011.
Millions more have been forced to flee their homes.