Can David Cameron achieve a new settlement for the UK within Europe? HARDtalk speaks to Sir Nigel Sheinwald who was the UK's top diplomat at the EU, foreign policy adviser to Tony Blair and then ambassador to the US.
He says that negotiating will not be easy: "It's going to be very difficult. When you're in a negotiation of 27, everyone wields a veto. Everyone's got a gun in the room."
You can watch the full interview on the BBC News Channel on Monday 28 January at 04:30 GMT and Tuesday 29 January at 00:30 GMT and on BBC World News on Monday 28 January at 04:30, 09:30, 14:30 and 21:30 GMT.
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