UN-Arab League mediator Lakhdar Brahimi suggested the Security Council consider an arms embargo on both sides of Syria's conflict during a closed-door meeting, a UN official said Wednesday.

Brahimi "emphasized the need for a political solution along the lines of the Geneva Communique and warned against the growing militarization and radicalization inside Syria," Under-Secretary-General for Political Affairs Jeffrey Feltman said, describing the address delivered Friday.

"He reiterated the secretary-general's call to stop the flow of arms to either side in Syria and called on the council to consider an arms embargo."

The United States was cool to the idea. State Department spokesman Patrick Ventrell said that while he had not seen Brahimi's remarks, "we haven't supported or come out and said that we want some sort of total arms embargo."

But Ventrell criticized weapons to the Syrian regime, saying that arms provided by Iran and Russia were "destructive" and "raining down on the heads of innocent women and children."

The Security Council has been deeply divided on the conflict, with Western nations pushing for tough action against Syrian President Bashar al-Assad and Russia opposed to any sanctions against its close regional ally.

Iran is believed to be supplying arms to Assad's regime while Saudi Arabia and Qatar are reportedly arming the rebels. The United States and European nations have until now provided only non-lethal aid to the opposition.

Feltman said Syrian authorities have yet to grant permission for a UN fact-finding team to investigate reports of chemical weapons attacks.

"We are still in discussions with the government of Syria on the scope and modalities of the mission," Feltman said, adding that experts are studying information provided by member states.

The experts "are ready to deploy to Syria within 24 to 48 hours following the Syrian government's acceptance," he added.

On Tuesday, the head of research and analysis in the Israeli army's military intelligence division said Assad had resorted to using chemical weapons, likely sarin, against rebel fighters.

"One of the characteristics of the recent period is the growing use by the regime of surface-to-surface missiles, rockets and chemical weapons," Brigadier General Itai Brun told a conference.

"To the best of our professional understanding, the regime has made use of deadly chemical weapons against the rebels in a number of incidents in the past few months," he added, in remarks quoted on the army's official Twitter feed.

The United States meanwhile said it has not yet concluded that Assad's regime has used chemical weapons against rebel forces, which President Barack Obama has long warned would be a "red line."