France and US say Syria is not like Iraq war

He noted that he "pushed" US intelligence to declassify intercepted messages on Syria "to make certain that this would not be Iraq 2."

"Those [intercepted] conversations confirm that the Assad regime issued orders to prepare for the attack, told their soldiers to prepare for chemical weapons, issued orders to have gas masks," he said, referring to Syrian leader Bashar al-Assad and his alleged use of sarin gas to kill hundreds of civilians on the outskirts of Damascus on 21 August.

"There will be no boots on the ground, no soldiers put at risk, no lengthy action, no long term - this is not Iraq, it is not Afghanistan, it’s not Libya, it’s not Kosovo," he added, referring to other US military interventions.

Fabius, in an emotional speech, recalled that France went against the US on Iraq because "the weapons of mass destruction did not exist."

He said: "This has nothing to do [with Iraq] … Here, weapons of mass destruction [do] exist and the fault, the mistake would be not to sanction them."

He added: "Each time the cause is just … we stand together, France and the United States."

Despite their rejection of the Iraq precedent, both men alluded to former US leader George W. Bush's notion of the "axis of evil" - Iran, Iraq and North Korea.

They said that if Syria gets away with chemical attacks it will make PyongYang and Tehran bolder in their pursuit of nuclear weapons.

They also compared al-Assad to the late Iraqi dictator Saddam Hussein and to Hitler.

Kerry and Fabius said they had the majority of world leaders on their side, despite ongoing opposition from Russia and China.

Kerry noted that 12 out of the G20 club of the world's richest nations signed a statement on Friday voicing "support" for a US-led coalition to "reinforce the prohibition on the use of chemical weapons."

He also noted that EU countries signed a joint communique on Saturday blaming al-Assad for the 21 August gas attack and urging a "clear and strong response."

"It’s a strong statement calling for strong action - not specifically military, but calling for strong action," Kerry said.

"It would be totally wrong to talk about isolation [of the US and France]," Fabius noted.

For her part, German Chancellor Angela Merkel, at an election rally on Sunday, explained why Germany did not sign the G20 statement on Friday, but waited until the EU communique was out on Saturday before adding its name to the G12 text.

"I don't believe it's right for five countries [the five EU states which are G20 members] to agree on a united stance without the other 23 that can't be there, knowing that 24 hours later all 28 will be gathering around the same table," she told press.

"That's why I said, 'Let's see to it that we [first] have a united stance by all 28'," she added.

The German intelligence service, the BND, also on Sunday shed light on what might have taken place on 21 August.

It told the mass-circulation weekly, Bild am Sonntag, that it has intercepted phone calls showing that al-Assad had rejected calls by his military chiefs to use gas and indicating that a rogue military commander might have ordered the 21 August attack.

With the US waiting for a vote in Congress and France waiting for a UN weapons inspectors report before taking action, the BND added that, even if they strike al-Assad, he is likely to remain in power and the civil war is likely to drag on for years.