Deputy National Security Adviser Ben Rhodes, US Ambassador to the UN Samantha Power, US Secretary of State John Kerry, and US President Barack Obama. Kevin Lamarque/Reuters In a meeting with members of Syria's opposition in Saudi Arabia on Saturday, US Secretary of State John Kerry demanded that rebels accept a set of preconditions dictated by Russia and Iran in order to participate in peace talks, according to an explosive report by the daily pan-Arab newspaper Al Hayat.

The terms Kerry reportedly asked the opposition Saudi-backed High Negotiation Committee (HNC) to accept — including a "national unity government" instead of a transitional governing body that would phase Syrian President Bashar al-Assad out of power — represent "a scary retreat in the US position," opposition sources told the head of Al Hayat's Damascus bureau, Ibrahim Hamidi.

According to translations provided by multiple Middle East analysts on Twitter, Kerry told the opposition delegation that, based on an "understanding" he had reached with Russian Foreign Minister Sergei Lavrov, Assad has the right to run for reelection and there will be no set timetable for his departure.

That stands in contrast to the White House's previous position that while Assad does not have to go immediately, the timing of his departure should be addressed during negotiations.

Kerry also signaled the Obama administration's endorsement of a four-point peace plan for Syria created by Iran, a staunch ally of Assad. The plan calls for an immediate ceasefire, the establishment of a national unity government, the anchoring of minority rights in the constitution, and internationally supervised presidential elections in Syria.

UN Special Envoy for Syria Staffan de Mistura. Thomson Reuters

UN Syria envoy Staffan de Mistura pushed for the national ceasefire on Monday, saying in a press conference from Geneva that "the condition is it should be a real ceasefire and not just local."

The ceasefire would apply to all warring parties but the ISIS and Al-Qaeda affiliate Jabhat al-Nusra. As Al Hayat has noted, that implicitly would grant legitimacy and "an official status" to the Shiite militias Iran has built in Syria to support Assad.

Including minority rights in the constitution, meanwhile, would serve as an attempt to "anchor sectarian tensions" between Sunni and Shiite Muslims within a legal framework.

These demands are "a desperate move" by the US to make the negotiations "look like progress," tweeted Hassan Hassan, coauthor of "ISIS: Inside the Army of Terror" and resident fellow at the DC-based think tank Tahrir Institute for Middle East Policy.

"De Mistura also echoed Russia's demands. Short-sighted of the US to think this will go well," he added.

So far, it is not going anywhere. Members of the HNC reportedly rejected Kerry's demands and have threatened to boycott the negotiations altogether. They reiterated that they will not attend the talks until the government halts air strikes and ends its sieges of rebel-held territory, in accordance with UN resolution 2254, adopted last month by the UN Security Council.

Protesters carry banners and opposition flags as they march in Aleppo, Syria, asking for the release of prisoners held in government jails and the lifting of the siege on besieged areas. Abdalrhman Ismail/Reuters

The terms of that resolution have failed to materialize, but Kerry apparently pressured the opposition into attending the talks anyway. Rebel sources told Al Hayat that Kerry went one step further and threatened to cut off US aid to rebel groups if they failed to show up at the negotiating table.

On Monday, Kerry reiterated that preconditions are a nonstarter for negotiations. But he categorically denied that he had threatened to cut off aid to the rebel groups.

"The position of the United States is and hasn't changed. We are still supporting the opposition, politically, financially and militarily," he said, according to The Associated Press. "We completely empowered them. I don't know where this is coming from."

He noted, however, that "it's up to the Syrians to decide what happens to Assad," effectively echoing Russian officials.

Nawaf Obaid, an Al Hayat columnist and visiting fellow at Harvard's Belfer Center for Science and International Affairs, further noted the meeting's most significant and "shocking" points in a series of tweets on Sunday:

While the HNC's senior negotiator, Mohammad Aloush, promised a "strong reaction" to these demands in a press conference on Sunday, HNC spokesman Salim al-Muslat told Reuters that the meeting with Kerry had been "positive" overall.

Former Syrian opposition leader Hadi Albahra noted, too, that the reports circulating about Kerry's requests for the HNC were "not fully accurate."

On Monday, however, de Mistura announced that talks will be postponed at least four days, to January 29, while negotiators work to resolve lingering disagreements over which members of the opposition will be invited to participate.

Kerry apparently stipulated that the HNC has to include certain Moscow-friendly opposition leaders into its delegation, including Kurdish PYD leader Saleh Muslim, former Syrian deputy Prime Minister Qadri Jamil, and Haitham Manna, exiled leader of the non-Islamist Syrian Democratic Council.

US Secretary of State John Kerry takes his seat across the table from Russian Foreign Minister Sergey Lavrov. Thomson Reuters

The Saudi-backed HNC has so far refused to expand its delegation, insisting that it represents all legitimate opposition players. In response, Bloomberg reported, the US and Russia are considering inviting a separate opposition delegation to the talks made up of rebel leaders Moscow has proposed and endorsed.

Middle East analyst Kyle Orton, an associate fellow at UK-based think tank The Henry Jackson Society, tweeted a grim analysis: "With the way things have stacked up, it's hard not to see it as Obama and Kerry consciously working for the defeat of Syria's opposition."

Hassan Hassan put it bluntly: "US officials are telling Syrians what extremists have been telling them for years — the US isn't your friend."