Brexit negotiations have been delayed by a week to give both sides more time to prepare, it has been confirmed.
The fourth round of talks, which were earmarked for September 18, have now been pushed back to the 25th.
Downing Street said on Tuesday the decision had been reached in order to afford negotiators the "flexibility to make progress" when discussions resume.
Reports from Brussels suggested the postponement was also agreed to accommodate Theresa May's plan for a major Brexit speech - expected on September 21.
It comes after International Trade Secretary Liam Fox warned the European Union should not "blackmail" Britain over the - as of yet unsettled - final Brexit bill.
Talks on future trade agreements can not commence until the issue of the divorce bill is finalised.
Whitehall sources insisted the new date was agreed mutually - adding that September 18 had not been fixed.
A Government spokesman said: "The UK and the European Commission have today jointly agreed to start the fourth round of negotiations on September 25.
"Both sides settled on the date after discussions between senior officials in recognition that more time for consultation would give negotiators the flexibility to make progress in the September round."
The next round of talks will now take place less than a month before a key EU summit.
On October 18, the remaining 27 EU states will assess whether sufficient progress has been made to move on to discussions on the future trade partnership.
Since talks began, Brussels has expressed frustration at several issues surrounding the UK's departure from the bloc.
These include the Irish border, citizens rights and the "divorce bill" - expected to be around £50 billion.
Following the third round of negotiations, Brexit Secretary David Davis admitted talks were "getting a bit tense".
Speaking after a speech in Washington DC, Mr Davis said talks had seen "tough" discussions regarding the size of the exit bill.
Mr Fox also said that Britain could not be "blackmailed" into paying.