Secretary of State Hillary Clinton said on Tuesday that the US would be taking "additional steps" against Syria.
Mrs Clinton said the Syrian government had "embraced the worst tactics of their Iranian ally, and they have refused to honour the legitimate aspirations of their own people".
"President Assad talks about reform, but his heavy-handed, brutal crackdown shows his true intentions," she added.
www.bbc.co.uk/news/world-middle-east-13444179