Updated

An International Atomic Energy Agency report on Syria's alleged clandestine nuclear activities has raised concerns the country violated its nonproliferation obligations, several Western ambassadors on the U.N. Security Council said Thursday.

U.S. Ambassador Susan Rice said her country's concerns were confirmed in the report delivered by the IAEA on Thursday to a closed council meeting.

The agency says Syria has refused to cooperate with an investigation of its alleged secret nuclear activities.

Rice charged that Syria's actions threaten peace and security and said "Syria's positive and prompt cooperation with the IAEA would be the best way to resolve outstanding questions about its nuclear program security."

Syrian U.N. Ambassador Bashar Ja'afari, who did not attend the closed meeting, told reporters outside council chambers that the charges of noncooperation were "prefabricated and unfounded."

The IAEA has tried in vain since 2008 to follow up on strong evidence that a site in the Syrian desert, bombed in 2007 by Israeli warplanes, was a nearly finished reactor built with North Korea's help.

Syria has said the facility was a non-nuclear military site.

The IAEA resolution that reported Syria to the Security Council expressed "serious concern" over "Syria's lack of cooperation with the IAEA Director General's repeated requests for access to additional information and locations as well as Syria's refusal to engage substantively with the Agency on the nature of the Dair Alzour site."

After the meeting, French Ambassador Gerard Araud declared in a tweet from France's U.N. mission Twitter account that "Syria has violated its nuclear nonproliferation international obligations."

The IAEA referred the issue several weeks ago to the council, which debated it without action Thursday afternoon.

Council agreement on a future resolution, including sanctions, on the Syrian nuclear issue seems unlikely. The council is empowered to impose sanctions such as arms embargoes, asset freezes and travel bans on individuals and entities to force compliance with international law.

Russia and China, both permanent council members with veto power, are among those countries that opposed the IAEA's referral.

Because of the council split, the body has also been unable to reach agreement in recent weeks on a draft resolution condemning the crackdown by Syria President Bashar Assad's government on the opposition.