US Secretary of State John Kerry talks to Russian Foreign Minister Sergey Lavrov before the start of a meeting on Syria, in New York on Friday, as UN Secretary General Ban Ki-moon looks on.

Reuters/United Nations

The five permanent members of the UN Security Council were struggling to agree on a draft resolution endorsing an international bid to end the five-year civil war in Syria, as ministerial talks began in New York on Friday.

Western powers had hoped the council would rubber-stamp a resolution endorsing a two-year road map for talks between Syria's government and opposition on a unity government, expected to begin in January, and eventual elections.

Council diplomats said they aimed to clinch an agreement on a text. But a deal remained elusive on Friday morning as talks among the 17 members of the so-called International Syria Support Group got underway at New York's Palace Hotel.

The 15-nation Security Council was scheduled to meet at 3 pm ET to discuss Syria, and it was not yet clear whether they would have a resolution to adopt.

The road map, which also calls for a nationwide ceasefire that would not apply to Islamic State, Nusra Front and some other militant groups, was worked out in two rounds of ministerial talks in Vienna.

Russian Ambassador Vitaly Churkin suggested there were significant disagreements on the draft resolution among the Security Council five veto powers - the US, Britain, France, Russia and China.

"I'm not sure it's going to happen because there are some unfortunately deliberate, or not deliberate, attempts to undercut the Vienna documents and we don't want to see that," he told reporters on Thursday without elaborating.

Diplomats said the main problem with the resolution involved Russian and Iranian concerns about how to refer to a bloc of opposition groups that would join UN-led peace talks with the Syrian government set to begin in January.

Saudi meeting

Western officials say a recent meeting in Saudi Arabia of opposition figures made significant headway in coming up with an opposition bloc, though Russia and Iran questioned the legitimacy of the Saudi-hosted discussions.

"Do not expect a breakthrough from this round of talks. Many differences remain, including differences on terrorist groups," an Iranian diplomat said on condition of anonymity.

The Riyadh conference agreed to set up a 34-member secretariat to supervise peace talks, and that committee will also select the opposition's negotiating team.

China's Foreign Minister Wang Yi warned that the political process could go backwards if no progress was made in New York.

"The two most important issues are the launch of the political negotiation and the other is the ceasefire," Wang added. "We hope this meeting can form a consensus on these two major issues and generate concrete actions."

German Foreign Minister Frank-Walter Steinmeier said there was "some movement" in the talks on Syria, adding that one goal of the New York meetings was to clarify the timeline for peace talks between the government and opposition.

Foreign ministers from 17 countries - including Russia's Sergei Lavrov, US Secretary of State John Kerry and other European and Middle Eastern ministers, as well as top diplomats from regional rivals Turkey, Saudi Arabia and Iran, were in New York for the Syria meetings.

Also present were UN chief Ban Ki-moon, his Syria envoy Staffan de Mistura and EU foreign policy chief Federica Mogherini.

Earlier this week diplomats said some progress had been made on the most difficult sticking point in the talks - the fate of Syrian President Bashar al-Assad.

They said Russia had indicated it had no problem with the eventual ouster of Assad at the end of a transition period, though it would not admit that publicly.