Brexit negotiations at an impasse over the issue of the divorce bill, with the UK refusing to name a figure.
The British team tells the EU its demands have no legal basis.
Talks will likely not be resolved by the October deadline, when "sufficient progress" needs to have been made on the bill, the Irish border and citizens' rights after Brexit.
LONDON – Brexit negotiations have hit a wall after the UK and EU negotiators failed to make any progress on how big Britain's withdrawal bill should be during "intense" talks, according to various reports.
The British team told their EU counterparts that there was no legal basis for much of the money they have claimed is required, while the EU has protested that Britain has failed to establish a clear position on the matter.
On Wednesday Barnier said: "To be flexible you need two points – our point and their point. We need to know their position and then I can be flexible."
This came after the UK negotiating team laid out their arguments on the issue of the divorce bill with a 23-slide presentation and 11-page document over three hours, and said that they cannot reach a figure until October at the earliest.
Britain's financial obligations to the EU, or the "divorce bill" as it's more commonly known, is one of the issues that the EU wants to finalise before talks on future relations take place, alongside citizens' rights and the Irish border.
The British side, on the other hand, claims that it is impossible to make "sufficient progress" on preliminary issues like the divorce bill without at the same time addressing what the future UK-EU relationship will look like.
"There was total amazement," a source within the EU told the Telegraph newspaper, describing discussions between British and EU negotiators.
"Everyone was completely flabbergasted that this young man from Whitehall was saying that the EU's preparation on the financial settlement was 'inadequate'. It did not go down well."
The British officials reportedly dismantled the EU's interpretation of the withdrawal bill, which is reported to be a figure of around £60 billion (€75 billion), although this figure never been confirmed by the EU.
Negotiations were not over specific figures, but on the way that the final sum will be calculated. Brussels believes that the EU's six-year budget should be used to calculate the figure, with Whitehall arguing that it should be decided based on annual budgets.
"The UK is not convinced that the European Commission’s paper [on the financial settlement] is satisfactory," a source told the Times newspaper. “Nobody would write a cheque on the basis of the Commission’s four-page paper."
Davis has previously said that while the UK "will meet any real international obligations... there won't be a number [agreed for the divorce bill] by October or November."
Some reports have suggested that the government is prepared to pay up to £36 billion in financial obligations, which Downing Street dismissed as "inaccurate speculation."
On Tuesday a poll conducted by Guardian/ICM revealed that more than 70% of voters think a bill of more than £30 billion would be unacceptable.