COPENHAGEN, Denmark: Secretary of State Hillary Rodham Clinton says the U.S. would need international support, including from Russia, for any military action in Syria.

Clinton says U.N. and international support made possible last year's intervention in Libya. She says Russia and China stand in the way of an international coalition against the government of Syrian President Bashar Assad.

Clinton told Danish students in Copenhagen that the U.S. hasn't given up on persuading Moscow to get tougher on Assad.

But she stopped short of saying a military response was necessary.

She said a larger civil war could make things worse and morph into a proxy war that draws in Iran and other regional powers.

Clinton spoke Thursday in Denmark's capital on the first leg of a weeklong trip to Europe.