Talks between Dominic Raab and EU chief negotiator Michel Barnier have failed to resolve key issues including the Irish border.
The Brexit Secretary met with Mr Barnier for negotiations on Sunday as the government continues to desperately secure a deal on leaving the EU.
However after the meeting, Mr Barnier said that there had been a failure to reach an agreement on one of the more complicated aspects of negotiations “despite intense efforts.”
The talks lasted just over an hour.
Mr Barnier said “some key issues are still open” including the backstop measure to prevent a hard border.
He said he would debrief the 27 remaining EU states and the European Parliament on the state of the negotiations.
Ambassadors for all EU member states, excluding Britain, were summoned to a meeting on Brexit at the same time as Mr Raab's talks were taking place.
A Dexeu/Number 10 spokesman said: "In the last few days UK and EU negotiators have made real progress in a number of key areas. However there remain a number of unresolved issues relating to the backstop.
"The UK is still committed to making progress at the October European Council."
Writing in the Sunday Times he said: "This is one of the most fundamental decisions that government has taken in modern times.
"It is time for the cabinet to exert their collective authority. This week the authority of our constitution is one the lane."
While on Saturday, former foreign secretary Boris Johnson said the current Irish backstop deal would be the UK's "greatest humiliation" since the Suez Crisis, while also repeating his Tory party call to "chuck Chequers."
Additional reporting by PA.