BBC – American forces are “ready” to launch strikes on Syria if President Barack Obama chooses to order an attack, US Defence Secretary Chuck Hagel says.
“We have moved assets in place to be able to fulfil and comply with whatever option the president wishes to take,” Mr Hagel told the BBC.
US Secretary of State John Kerry has said there is “undeniable” proof that Syria used chemical weapons.
The UK Parliament is to be recalled on Thursday to discuss possible responses.
Prime Minister David Cameron, who has cut short his holiday and returned to London, said MPs would vote on a “clear motion” on the crisis. Syria’s allies, Russia and China, have stepped up their warnings against military intervention in Syria, with Moscow saying any such action would have “catastrophic consequences” for the region.
Syrian Foreign Minister Walid Muallem has said he rejects “utterly and completely” claims that Syrian forces used chemical weapons.
His government has blamed rebel fighters for the latest suspected chemical attack, which took place on 21 August near the Syrian capital Damascus and reportedly killed more than 300 people.
On Monday, United Nations chemical weapons inspectors were fired on while investigating one of the five alleged chemical weapons attack sites around Damascus.
Mr Hagel said the US Department of Defence had provided President Obama with “all options for all contingencies”.
“He has seen them, we are prepared,” he told the BBC’s Jon Sopel, adding: “We are ready to go.”
Mr Hagel said that intelligence currently being gathered by the UN inspectors would confirm that the Syrian government was responsible for the chemical attack last week.
“I think it’s pretty clear that chemical weapons were used against people in Syria,” he said. “I think the intelligence will conclude that it wasn’t the rebels who used it, and there’ll probably be pretty good intelligence to show is that the Syria government was responsible. But we’ll wait and determine what the facts and the intelligence bear out.”
Mr Hagel’s remarks come a day after Mr Kerry accused the Syrian government of destroying evidence of its chemical weapons use near Damascus by shelling the area.
He said his administration had additional information about the attacks that it would make public in the days ahead. Mr Kerry described the assaults as a “moral obscenity”.
“What we saw in Syria last week should shock the conscience of the world. It defies any code of morality,” Mr Kerry said at a news conference on Monday.
“Make no mistake, President Obama believes there must be accountability for those who would use the world’s most heinous weapons against the world’s most vulnerable people.”
Meanwhile, warnings have been issued on sites linked to Islamic militants fighting for the rebels in Syria, saying that their leaders and training camps might also be targeted by a possible US-led attack.
Several online sites linked to the Nusra Front and similar groups have advised militants not to hold meetings or gather in large numbers, and to change routines and locations.
Western powers have made clear their distrust and dislike of groups like the Nusra Front, which have spearheaded rebel victories, although there has been no indication from the US or anyone else that jihadists would be targeted.
The UN says more than 100,000 people have been killed since the uprising against President Assad began more than two years ago. The conflict has produced more than 1.7 million registered refugees.