David Cameron has pledged an in-out referendum on Europe in 2017, and says he will not lead the country if he cannot guarantee to provide the vote.
The prime minister's comments, made on BBC One's The Andrew Marr Show, suggest he would not lead a minority government should the Conservatives fail to secure a parliamentary majority at the 2015 General Election.
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As Princess Charlotte celebrates her first birthday on Monday, the young royal has received letters and gifts from 64 countries worldwide.
A 36-year-old man has been shot dead during a police operation in Kent.
Brussels' Zaventem Airport departure hall has reopened to the public, 40 days after twin suicide attacks killed 16 people.