New York: US Secretary of State John Kerry told Syrian opposition leaders that they risked losing their funding if they did not attend peace talks, according to Syrian opposition leaders and administration officials.

On Saturday in Riyadh, Kerry met representatives of the High Negotiating Commission, the opposition’s representatives, to meet this week in Geneva with the Syrian regime. Afterwards, opposition leaders faulted Kerry’s efforts, saying he had tried to “pressure” them into giving up longstanding demands. They have insisted that the Syrian dictatorship stop aerial bombardment and starvation sieges of civilian towns, before the opposition sits down with the regime.

Arabic press reports portrayed Kerry as “carrying the dictates of Russia and Iran” and trying to impose them on the Syrian opposition. They said Kerry was moving towards the Russian-Iranian position in several ways, including by expressing support for a “government of national unity” that would usher in elections in which the current president, Bashar Al Assad, could run.

After the meeting, Kerry was upbeat about the talks and said he would do everything he could “to try to push this process forward and help to act as constructive catalysts in trying to help the Syrians to bring about the peace that they desire so much”. But opposition leaders said he went too far by threatening them with a loss of international support.

“Kerry said it in the context that if they don’t go, it will affect their public image and this may affect the aid they receive from their friends,” said Hadi Al Bahra, the former president of the Syrian National Coalition. “It was more speculation than a direct warning, but people understood this as a threat.”

A US administration official confirmed that Kerry told the High Negotiating Commission leaders that their support would be re-evaluated if they didn’t attend the upcoming Geneva talks. The Geneva meeting was supposed to start on Monday but is now delayed until Friday. The commission is meeting again on Tuesday to discuss the issue.

In addition to their concerns about the humanitarian situation and the lack of assurance that Al Assad will go, the commission is also complaining that Kerry is pressuring them to accept unwanted additions to their negotiating team.

The High Negotiating Commission is the broadest representation of Syrian opposition groups yet, but Russia is pushing for it to add Kurdish representatives from the PYD (Democratic Union Party) and also opposition figures who have close ties to Russia, including Haitham Manna and Qadri Jameel, two Syrian figures who have lived in Moscow.

Russia is intentionally trying to undermine the prospects of a real negotiation where progress between the regime and the opposition could take place, said Al Bahra. Both sides should have equal power, so Moscow is trying to dilute the opposition by implanting its own proxies.

“The opposition should have equal power same as the regime delegation,” he said. “The only way to get around it for Russia and Al Assad is by really infiltrating the opposition delegation itself or by having multiple delegations. This way they can break the unity of the opposition and achieve whatever they want.”