The Queen led the UK's Holocaust Memorial Day commemoration on Thursday.

She was joined by the Duke of Edinburgh, leading politicians and religious leaders at a service in Westminster Hall.

Tony Blair, who backed the establishment of Holocaust Memorial Day five years ago, spoke of a suffering beyond imagination.

Tory leader Michael Howard, who lost his grandmother in the death camps, was in the audience.

The chief rabbi, Jonathan Sacks, said prejudice and intolerance should be challenged to ensure that nothing comparable can happen again.

"The survivors have borne the weight of memory. Now we must carry it and hand it on to our children," he said.