Annan plan 'should be compulsory'

France will propose giving the United Nations the power to enforce UN envoy Kofi Annan's Syrian peace plan, Foreign Minister Laurent Fabius said on Wednesday, adding that a no-fly zone was an option under consideration to stem what was now a civil war.

His comments were the toughest yet from a major power in response to the violence in Syria.

"We need to move up a gear at the Security Council and place the Annan plan under Chapter 7," which can authorize use of force, Fabius said. "That is to say, make it compulsory under the pain of very heavy sanctions."