America's top military officer has told his counterparts in South Korea that the United States is ready to use the "full range" of its military capabilities to defend itself and its allies from any North Korean provocation.

Government troops retreated to the outskirts of Misrata under rebel fire today and the opposition claimed victory after officials in Tripoli decided to pull back forces loyal to Muammar Gaddafi following nearly two months of laying siege to the western city.