The US says American forces are now prepared for any action ordered against Syria.
President Barack Obama has yet to give the order for military intervention, in response to a chemical attack in Damascus last week which left hundreds of people dead.
It's claimed the attack was carried out by Syrian government forces.
The British Prime Minister has recalled his parliament for tomorrow to debate and vote on the UK's response.
David Cameron has warned that the world cannot stand "idly" by - as the Syrian regime carries out "appalling" killings - with blatant disregard for life, and International Law:
