In a ceremony at NATO's northern European command headquarters, US General James Jones, NATO's top military chief, handed over the colours of the new force to its first commander, British General Jack Deverell.

"The passing of the colours... to General Deverell will mark what I consider to be one of the most important changes in the NATO alliance since the signing of the Washington Treaty," which founded NATO in 1949, Jones said.

The force represented "an unambiguous commitment of the alliance's intent to stay militarily relevant in a global context", the US supreme commander added.

"For the first time in its history the alliance will have a joint/combined air, land and sea and special operations force under a single commander."

US ambassador to NATO Nicholas Burns said: "The NATO Response Force is an important, innovative new military capability for NATO, and further evidence of NATO's on-going transformation to meet the new threats from global terrorism."

The force, designed to deploy to hotspots around the globe within five days, will eventually total 20,000 troops when it reaches full capacity in 2006.

The contingent represents a radical departure for the 54-year-old Alliance from its roots as the West's protector from the Soviet threat.