The Foreign Secretary Philip Hammond has said there are "still a lot of moving parts" in a renegotiation deal on Britain's membership of the European Union.
Speaking to the BBC's Andrew Marr Show, Mr Hammond said: "There are still a lot of moving parts in this discussion but it's already clear that we're going to get a clear statement that Britain is outside obligations of ever closer union."
Mr Hammond added that he was in no doubt "we'll run to the wire with some of these things only being able to be decided by the heads of state and government on Friday".
He also insisted that prior to the in/out referendum, the agreed package will have to be looked at “as a whole”.
“The point of having a referendum is that everybody will make up their own mind about whether the package, on balance taking the rough with the smooth, is in Britain’s interest or not”.
The United States would like to see "a very strong United Kingdom staying in a strong EU", secretary of state John Kerry has said.
Mr Kerry said it was "profoundly" in America's interests that the UK voted to remain in the union in the upcoming referendum.
David Cameron's renegotiation drive is approaching its moment of truth at a Brussels summit next week.
Speaking at a security conference in Munich, Mr Kerry said: "I want to express the confidence of President Obama and all of us in America that, just as it has so many times before, Europe is going to emerge stronger than ever, provided it stays united and builds common responses to these challenges.
"Now obviously, the United States has a profound interest in your success as we do in a very strong United Kingdom staying in a strong EU."
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