A DECISIVE showdown between Boris Johnson and Parliament over his "do-or-die" promise to deliver Brexit month is to take place on October 19.

It will be the first Saturday sitting of the Commons since the Falklands crisis of 1982.

The special sitting falls two days after the EU summit which is the Prime Minister’s last chance to secure a Brexit deal before his October 31 deadline.

If, as seems increasingly likely, he fails to get a deal, the emergency Benn Act legislation requires him to seek an extension of at least three months from EU leaders.

The PM has said he would rather “die in a ditch” than do that, but has also promised to obey the law.

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The October 19 sitting would therefore be the moment he has to set out how he intends to solve this apparent contradiction, perhaps by sending a second letter to the EU undermining the one he is obliged to send by the Benn Act.

There are also reports the PM might try to force MPs to vote on whether to revoke Brexit or even invite a no-confidence vote in an attempt to have an election.

However, MPs could try to seize control of the order paper to frustrate him.

The opposition parties and Tory rebels could also, in theory, form a temporary government of national unity in order to request the Brexit extension if Mr Johnson tried to dodge it.

Mr Johnson presented his alternative proposal to the Irish backstop to the EU last week.

Although some elements were welcomed in Brussels, there were concerns over the need for customs check on the islands of Ireland.

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Mr Johnson proposed keeping Northern Ireland aligned with EU single market rules but taking it out of the customs union, creating the need for customs checks.

His plan also gives the pro-Brexit DUP an effective veto over the single market element.

Relations between the UK and EU then appeared to nosedive yesterday when Number 10 briefed a deal appeared “essentially impossible”.

It followed a “frank” phone call between Mr Johnson and German Chancellor Angela Merkel, in which Downing Street claimed she had called the idea “overwhelmingly unlikely” to work.

Labour accused Number 10 of trying to put the blame for the failure of talks on the EU, and said Mr Johnson’s plan had never stood any chance of success.

The president of the EU Council Donald Tusk then tweeted directly as Mr Johnson, telling him the future of the UK was at stake, and not to play some “stupid blame game”.

After meeting Mr Johnson in Downing Street on Tuesday, EU Parliament President David Sassoli also reported there had been “no progress” on a deal.

He also stressed the UK would be to blame for a no-deal Brexit.

European Commission Jean-Claude Juncker also told the French newspaper Les Echos that the UK was engaged in a “blame game”, adding: “A no-deal brexit would lead to the collapse of the United Kingdom”.

With Dublin’s opinion seen as holding great sway within the EU, Mr Johnson also spoke to Taoiseach Leo Varadkar for 40 minutes on Monday. 

However the Irish PM then told the broadcaster RTE a deal would be “very difficult” by Hallowe’en and “big gaps” remained between the two sides.