The United States and its allies were today moving to seal off potential escape routes - even at sea - for terror chief Osama bin Laden.

Afghan warlords have a long tradition of changing sides in mid-battle, and none has switched teams more often than Rashid Dostum, the gruff and burly leader of an ethnic Uzbek faction.

The Taliban has ceased to function as an effective government, America claimed tonight as the rebel Northern Alliance stepped up its assault on one of the regime’s key strategic strongholds.