George Osborne has defended the deal that will leave Britain paying an extra £850 million towards the European Union budget, insisting it was a "real win" despite accusations he has resorted to "smoke and mirrors".
Critics claimed the reduction in the £1.7 billion bill had been achieved by bringing forward a rebate to which the UK would have been entitled anyway.
But the the Chancellor insisted there had been "real doubt" over whether that clawback would apply to the surcharge.
He told BBC Radio 4's Today programme: "The truth is, as always, we have achieved a real win for British taxpayers and having achieved it everyone says 'oh, of course you were always going to achieve that'.
"But it took a lot of hard discussion, a lot of hard negotiation and it shows that when this government sets out a goal in Europe it goes and achieves it."
But his claims follow Ukip leader Nigel Farage suggesting the Chancellor was not being entirely honest.
"Osborne (is) trying to spin his way out of disaster," he said. "UK still paying full £1.7 billion, his credibility is about to nose-dive.
"Borrowing what we are rightfully owed in the future to pay an unfair bill being levied now is not a victory. It's a sham."
Shadow Chancellor Ed Balls also weighed into the argument, saying that the Prime Minister and his chancellor are "trying to take the British people for fools."
Ministers have failed to get a better deal for the British taxpayer," he said.
"Not a single penny has been saved for the taxpayer compared to two weeks ago when David Cameron was blustering in Brussels.
"By counting the rebate Britain was due anyway, they are desperately trying to claim that the backdated bill for £1.7 billion has somehow been halved. But nobody will fall for this smoke and mirrors.
"The rebate was never in doubt and, in fact, was confirmed by the EU Budget Commissioner last month."
Mr Osborne said it was "not clear" that the rebate was going to apply to the surcharge, which was demanded after a recalculation of Britain's gross national income (GNI) relative to the other 27 member states, until the deal was struck in a summit with fellow EU finance ministers in Brussels.
"It was a real doubt about whether the rebate would apply, apply to the extent it has applied. We have got this bill halved."
Asked if Britain's contributions to the EU were value for money, he replied: "I don't think we get full value for money for all those pounds that get sent to the European Union."
Labour has claimed the deal does not save the UK "a single penny" and accused Mr Osborne and the Prime Minister of "trying to take the British people for fools".
The Chancellor's European counterparts also appeared to contradict the Chancellor's account of the deal.
Irish finance minister Michael Noonan said he believed that the UK "will pay the whole amount" while Dutch finance minister Jeroen Dijsselbloem said "it's not as if the British have been given a discount".
The European Commission's vice-president with responsibility for the budget, Kristalina Georgieva, said the additional contribution being demanded from the UK meant that its rebate was also increased, leading to a "downward correction" in the overall sum to be paid.