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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Northern Ireland's Health Minister Jim Wells has quit after sparking controversy over comments about gay marriage.
Prince Harry may not be able to meet his new niece or nephew until mid-May unless the royal baby puts in a speedy appearance.
A British climber trapped on Mount Everest after the earthquake in Nepal has said rescuers face "a race against time" to reach his group