The Prime Minister said today that it is in the national interest to be part of the European Union but that this doesn't mean it cannot opt out of certain measures.
Speaking at the European Summit in Brussels, he said there was a "false choice" between going along with all of the reforms of the Union and leaving it.
Asked whether there is a growing impression that Britain is not interested in the EU, David Cameron said he has a reputation for plain speaking but is not anti-EU.
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The so-called Islamic State group has released a video, which purportedly features a British boy, appearing to execute a prisoner.
The two-year-old's condition is said to be "life-threatening" after he was struck by a car while out walking with his grandfather in London.
Lord O'Donnell, who used to head up the Civil Service, says he believes Britain may not actually exit the European Union.