Britain's Prime Minister Boris Johnson | Isabel Infantes/AFP via Getty Images UK opposition parties agree to block October Brexit election Efforts should continue to secure a no deal, then a vote can be called, say MPs.

LONDON — U.K. opposition MPs agreed that Boris Johnson must bring into force a Brexit extension before they will back a general election.

The decision means that Johnson will not win the two-thirds backing for an election that he needs when he brings the issue to a vote for a second time in parliament on Monday. The first attempt to secure backing for an election failed on Wednesday.

Figures from Labour, the Scottish National Party, the Liberal Democrats and Plaid Cymru said a conference call between opposition parties on Friday morning ended with agreement that Johnson must be made to bring into effect legislation that forces him to seek a delay to Brexit if he has no agreement with the EU in place by mid-October.

Labour said MPs discussed "advancing efforts to prevent no-deal Brexit" and to hold an election "once that is secured."

If there was an election in mid-October, as Johnson wants, it remains a possibility that if he wins a majority, he could override the Brexit extension legislation and take the U.K. out of the EU without a deal on October 31.

The opposition parties now look set to withhold support for an election until after October 19, the day on which, according to the no-deal blocking legislation, Johnson must seek an extension from the EU until January 2020. All the parties insist they still want an election, but their decision means that a national poll now looks unlikely to be held until November at the earliest. Under the U.K.'s Fixed Term Parliaments Act, once a two-thirds majority backs it, an election must be held 25 working days after the dissolution of parliament.

The SNP's Westminster leader Ian Blackford told the BBC: “He should actually withdraw this motion on Monday because it’s going nowhere."

A Liberal Democrat official said: "There was agreement around the table that Boris can't be allowed to cut and run. Everybody got to the point that there should be no election until there is a guarantee of Article 50 being extended ... Therefore come Monday the government will lose on their vote for a general election and I don't expect there to be a general election before October 31."

Plaid Cymru's Westminster leader Liz Saville Roberts told the BBC that in October MPs' "duty … is to be [in parliament] to hold him to account and to make sure that he abides by that law.”

Parliament will be suspended from next week until October 14.

Johnson, who insists he will not ask for a delay to Brexit from the EU (on Thursday he said he would rather be "dead in a ditch") now must decide whether to abide by the law or seek an election through other means. His options are narrow and he has refused to say whether he would sooner resign than delay Brexit — a course of action which could lead to an election if no alternative government can be formed.

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