Cameron announced in his Bloomberg speech that a Conservative government would hold an in-or-out referendum on EU membership

On 23 January 2013, under pressure from many of his MPs and from the rise of UKIP, Cameron announced in his Bloomberg speech that a Conservative government would hold an in-or-out referendum on EU membership before the end of 2017, on a renegotiated package, if elected in the 7 May 2015 general election.