Nick Boles, who quit the Tory party over the threat of a hard Brexit, suggested the device could be used to suspend parliament for a general election – to be held after the UK has left the EU on 31 October.
It came as Mr Boles urged Jeremy Corbyn to guarantee he will not vote for a snap election if it were to be held after the Halloween deadline.
In a letter to the Labour leader, he rejected Mr Corbyn’s call for cross-party talks on blocking no-deal next week, instead arguing for legislation to force an extension to Article 50.
The prime minister has refused to deny that No 10 is plotting a post-Halloween election, if he is defeated in a vote of no confidence in the Commons as early as next month.
In his letter, Mr Boles agrees this could be “contrived” by the government, under the fixed term parliaments act, by two-thirds of MPs voting for it.
But he adds: “Or it could lay a motion of no confidence in itself, instruct Conservative MPs to abstain so that the motion passes, and then do everything in its power to obstruct the appointment of a new prime minister at the head of a new government within the following 14 days.”
Mr Boles warns: “It is clear that....the Johnson government will seek to engineer the prorogation of parliament for an early election to be held on 1 November.”
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Ruling out backing Mr Corbyn as a caretaker prime minister, the now-independent MP instead demanded a guarantee that Labour would never play along, to prove the “sincerity” of his opposition to no-deal.
“It is therefore essential that you declare publicly that you will not facilitate an election before an extension of Article 50 has been secured and a no-deal Brexit has been averted,” Mr Boles wrote.
Labour has condemned the idea of a post-exit election and left open the option of supporting an alternative caretaker prime minister, to its leader, to do “everything necessary” to avert a crash-out.
The Boles letter underlines the divisions at parliament between the anti-Johnson forces wanting an early no-confidence vote – and those favouring legislation to bind the prime minister’s hands.
No 10 anticipates an attempt – on 9 September – to force an Article 50 extension, but MPs are divided on how exactly to do that and over whether the endgame is an election or a Final Say referendum.
Opposition parties have agreed to attend the meeting Mr Corbyn has called for next Tuesday, with the Liberal Democrats, SNP, Plaid Cymru, the Green Party and The Independent Group for Change all signed up.