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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The twin brother of the police officer shot and blinded by gunman Raoul Moat says his family are still waiting for justice five years later.
The success of the No camp is mainly due to Tsipras convincing people a No vote will strengthen their hands in negotiations.
As we move into the weekend, expect things to get rather more unsettled weather-wise - thought it will stay hot and humid for some.