ITV News' Libby Wiener reports from Sao Paulo in Brazil where Prime Minister David Cameron is on a two-day visit.
The Conservative, who appeared on America's Late Show with David Letterman on Wednesday night, was quizzed by the veteran host over his knowledge of British history.
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Actor Pierce Brosnan was stopped by airport security after trying to board a plane with a knife.
Children are risking their lives by playing "chicken" on motorways during the school summer holidays, police say.
Dramatic footage has shown the moment a policeman pulled a man to safety just seconds a train smashed into his car.