World 'must tackle space threat'

The international community must work together to tackle the threat of asteroids colliding with Earth, a leading UN scientist says.

Professor Richard Crowther's comments come as a group of space experts called for a co-ordinated science-led response to the asteroid threat.

The Association of Space Explorers (ASE) says missions to intercept asteroids will need global approval.

The UN will meet in February to discuss the issue.