Kerry told television interviewers on Sunday the US had proof from sources independent of the UN inspection team that Syria used the nerve agent sarin in the August 21 bombardment of the Ghouta neighbourhood of Damascus.

Obama took all by surprise on Saturday by saying Congress would be consulted about strikes on Syria.

Significantly, he had not warned either Kerry or Defence Secretary Chuck Hagel that he had decided to consult the lawmakers before ordering US forces into action.

British Prime Minister David Cameron ordered naval and air force units to stand down and return to normal duties. The instruction came ahead of last week Thursday's Commons debate to ready themselves for strikes on Syria.

Like Kerry, Cameron and President Francois Hollande of France have also been playing hard cop to Obama's soft cop. But even that picture is changing. With French opinion polls showing a majority against military action, the French legislature is to be consulted now.

Despite Kerry declaring that the US had the full support of its "oldest ally" France, in Paris Interior Minister Manuel Valls stated bluntly: "France cannot go it alone, and we need a coalition."

Turkey is the only Nato ally so far to declare openly that it wants action to promote regime change in Damascus.

The mood swing across the Western alliance is that the idea of "a narrow, limited operation" in Obama's formulation does not work. Some remarkable, and unexpected, voices have warned of this - including former US Defence secretary Donald Rumsfeld, architect of the ill-fated incursion into Iraq, and Senator John McCain, who came out of a classified intelligence briefing at the weekend sceptical about Obama's strategy, despite having previously urged an attack.

"Once you start down this road, you can't get off it and maintain political credibility," warned the veteran diplomat Ryan Crocker, who has been US ambassador in Syria, Iraq and Afghanistan.

"We are pretty ignorant about Syria," he told the New York Times, adding that punitive missile raids rarely work.

In 1998, then president Bill Clinton ordered Tomahawk strikes against sites in Sudan and Afghanistan after the bombings of American embassies in Kenya and Tanzania by al-Qaeda. One of the missiles went to Pakistan by mistake, others hit a perfume factory in Khartoum, and Osama bin Laden and his clique escaped.

Professor Farwaz Gerges, who heads the Institute for the Middle East at the London School of Economics, told the BBC he believed the leaders of the Western alliance had not thought out the second and third level of consequences of a US strike.

Not only would a US strike lengthen the civil war in Syria, it would tip the hand towards the most violent and active rebel cohorts loyal to the al-Qaeda cause. Some of these are already using Syria to mount a major offensive into Iraq - where more than 500 have been killed in bombing attacks in under a month.

Any widening conflict is likely to involve Israel and Iran, Syria's principal ally in the region and the Shia-Sunni contest would encourage al-Qaeda activities in Yemen, Egypt and beyond. - The Week/First Post

DON'T BACK BARACK, SAY RUSSIAN MPs

RUSSIAN MPs want to travel to Washington to urge the US Congress not to back President Barack Obama's plan for military strikes on Syria, the speaker of the upper house of parliament told President Vladimir Putin yesterday.

Dismissing US accusations that the Syrian government had killed hundreds of its own people with poison gas as nothing but "talk", senior legislator Valentina Matviyenko said both chambers were ready to send delegations.

Russia is one of the main allies of Syrian President Bashar al-Assad and has already blocked several Western-led resolutions in the UN Security Council to sanction him for his crackdown on an uprising that has lasted for more than two years. It says it believes rebels launched the sarin gas attack.

Matviyenko told Putin : "We hope the US Congress will take a balanced position and, without strong arguments in place, will not support President Obama's proposal to use force in Syria." - Reuters