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US's 'difficult choices' over Syria

The United States is stepping up its direct military support for the Syrian opposition after saying it is confident that the Assad regime has used chemical weapons against its own people.

The White House says that up to 150 people have been killed in the attacks.

A spokesman said the deployment of chemical weapons had crossed "clear red lines''.

Speaking to Today programme presenter John Humphrys, PJ Crowley, who served as Mr Obama's assistant secretary of state for public affairs, said there would have to be a lot of consideration before military support is given to the rebels:

"Will the weapons stay in the right hands? And will the weapons stay in Syria? So some very difficult choices with regard to anti-armour weaponry or ground to air weaponry that could neutralise the Syrian air advantage but at the same time could migrate somewhere and threaten civilian aviation."

"These will be difficult calculations that the administration will make," he added.

First broadcast on BBC Radio 4's Today programme on Friday 14 June 2013.