Biden rebuffs Afghan questions: 'I want to talk about happy things'

The president was in no mood to be pressed by journalists about his order to withdraw US troops from Afghanistan, ending America's longest war.

He defended the pull-out on Friday as "nothing unusual", before refusing to another anymore questions from White House reporters about his decision.

The exit of all US forces from Bagram Air Base comes as Taliban fighters advance across the country, which US officials concede may be heading for civil war.