MPs are to be summoned to Parliament on a Saturday to discuss how to deliver Brexit.
Government ministers are expected to hold an emergency sitting of Parliament on October 19, following next week's crucial EU summit.
The summit in Brussels on October 17 and 18 is the last scheduled meeting of EU leaders before October 31- the date the UK is set to leave the EU.
Under legislation passed by MPs last month, prime minister Boris Johnson is legally obliged send a letter to the EU asking for an extension to Brexit if a deal cannot be agreed by October 19.
But in recent weeks the prime minister has hinted at finding away around the Benn Act saying that Britain will leave the EU on October 31 "deal or no deal".
His hopes of agreeing a withdrawal deal with EU leaders were dashed yesterday after a phone call with German Chancellor Angela Merkel, who reportedly told him a deal that took Northern Ireland out of the customs union was "essentially impossible".
A source for No 10 said she claimed a deal would be "overwhelmingly unlikely" under Mr Johnson's current plans, and added that talks were "close to breaking down".
Mr Johnson is expected to meet Irish Premier Leo Varadkar on Thursday (October 10) in a last-ditch effort to break the deadlock over the Northern Ireland backstop, which continues to stand in the way of an agreement.
But after speaking to Mr Johnson by telephone on Tuesday, Mr Varadkar warned that it would be "very difficult" to get an agreement in time for next week.
If a deal can not be agreed, it is expected that Mr Johnson will use next Saturday's sitting to lay out plans for a no deal Brexit on October 31.
Since the Second World War, MPs have been summoned to Parliament on a Saturday just four times, most recently to discuss the invasion of the Falkland Islands in 1982.
