Staffan de Mistura, U.N. special envoy for Syria, has urged Syrian opposition groups to attend the talks in Geneva. (Ronald Zak/AP)

Peace talks aimed at ending the Syrian war got off to a rocky start Friday, with the opposition saying it would send a team to consult on the goal of the negotiations but still refusing to commit to attend them.

The announcement by the opposition that it would send a fact-finding team to consult with the United Nations came at the end of a confusing day during which U.N. officials declared that the talks had officially opened even though the delegation opposed to President Bashar al-Assad had not shown up.

The disarray cast into doubt prospects for a successful outcome to a process that has been touted by the Obama administration as a foreign policy priority for the year ahead.

“There’s a lot riding on this diplomatic process, and it’s why the United States is so invested in it,” White House press secretary Josh Earnest said shortly before the opposition’s decision to send the team was announced, reflecting growing impatience within the Obama administration at the opposition’s hesitation.

The United States has been pinning hopes on the talks because, for the first time in Syria’s nearly five-year-old crisis, Russia, the United States, Saudi Arabia and Iran — the chief sponsors of the rival groups on the battlefield in Syria — had agreed on a road map for negotiations that was subsequently endorsed by a U.N. Security Council resolution in December.

The talks snagged even before they began, however, on a range of issues that go to the heart of the complexities of the war.

Central to the opposition’s reluctance to attend is the failure so far to implement two clauses in the U.N. resolution calling on all the parties to “immediately” allow humanitarian agencies access to people living in besieged communities, release political prisoners and halt airstrikes against civilian areas.

Instead, Russian and Syrian government forces­ have stepped up their attacks on opposition territory and people have begun dying of starvation in some of the communities under siege by government ­forces.

The medical charity Doctors Without Borders announced that since a single delivery of aid to the besieged town of Madaya, outside Damascus, nearly three months ago, 16 more people had died of starvation, bringing to 51 the number who have died from lack of food since December.

The opposition decision to send at least an advance team of delegates followed intense pressure from U.S., U.N. and other international figures, including telephone calls on Friday by Secretary of State John F. Kerry and Russian Foreign Minister Sergei Lavrov to the head of the opposition’s negotiating committee, Riyad Hijab.

Kerry “made clear” that implementation of those articles is “necessary by all parties,” State Department spokesman John Kirby said. Kerry believes that “it is important for these talks to happen, and important for the HNC to attend . . . without preconditions,” Kirby repeated several times, referring to the High Negotiating Committee, the group formed to represent the opposition in Geneva.

The talks, he said, will provide “an opportunity to test regime intentions.”

The team is expected to arrive on Saturday, opposition officials said, and although the opposition delegation still has not agreed to participate in the talks, the decision to send some representatives opened the door to fuller participation in the days ahead.

The U.N. special envoy for Syria, Staffan de Mistura, who is leading the negotiation effort, told reporters that he hoped by Sunday to be able to meet with the delegation.

“My feeling is — I may be wrong — that their internal discussion is leading towards accepting” to participate in the talks, he said.

De Mistura, meanwhile, met with the official Syrian government delegation, which showed up Friday morning headed by Bashar Jaafari, the Syrian ambassador to the United Nations.

Jaafari did not speak to reporters as he swept into the Palais des Nations, as the U.N. headquarters in Geneva is called, trailed by other members of the Syrian delegation.

But the official Syrian news agency SANA quoted him as saying that he had focused his discussions with de Mistura on the question of defining who is a terrorist in Syria’s war.

“Jaafari noted that there are sides which use the label ‘moderate opposition’ to describe foreign terrorists,” SANA said, suggesting that it is still not certain the government will agree to negotiate with members of the opposition, if they show up.

Russia, Syria and Iran have repeatedly labeled the opposition delegation “terrorists,” prompting de Mistura to downgrade the format of the negotiations to “proximity” talks. That means there will be no face-to-face meetings in any case between the government and the opposition.

Rather, they will gather in separate rooms with U.N. officials shuttling between them, a formula that could make it harder to create meaningful breakthroughs, at least in the near term.

DeYoung reported from Washington.

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