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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Nigel Farage has suggested a former Ukip candidate used the terms "chinky" and "poofters" because of his "council estate background".
Those who turned up late were turned away and told they weren't allowed to see their own children's carol concert.
Pakistan have released intelligence of the final conversations by the Taliban attackers responsible for the Peshawar school massacre.