David Cameron on Syria: ' Chemical weapons indefensible'

British Prime Minister David Cameron has said "the world shouldn't stand idly by" while the Syrian government uses chemical weapons on its own people.

He said no decision had been taken on whether to launch military action against Syria, but "I don't believe we can let that stand."

He added that any response would have to be legal, proportionate and aimed specifically at deterring the future use of chemical weapons.