The Pentagon is moving naval forces closer to Syria in case President Barack Obama decides to order military strikes, US Defence Secretary Chuck Hagel has suggested.
Speaking to reporters aboard his military aircraft en route from Hawaii to Malaysia, Mr Hagel declined to discuss any specific force movements.
He said Mr Obama has asked the Pentagon to provide military options in light of reports that the Syrian government used chemical weapons against civilians.
Mr Hagel said the US will coordinate with the international community in deciding whether such an attack was carried out.
And he said it is important to make a decision swiftly because of the possibility that the Syrian government could be readying further chemical attacks.