Pentagon spokesman John Kirby told NBC News there was "no reason to doubt the authenticity" of the clip purporting to show US soldier Sergeant Bowe Bergdahl, who has spent five years in Taliban captivity, being handed back into US custody.
He said: "US officials are currently reviewing the video, but our focus right now is in getting Bergdahl the care he needs."
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Lord O'Donnell, who used to head up the Civil Service, says he believes Britain may not actually exit the European Union.
The Labour leader said he doesn't believe culture should be just for the elites.
Rain will spread into southern and central England but elsewhere will remain dry with warm sunny spells.