The prime minister is considering a move to scupper any Brexit delay by simultaneously asking the EU for an extension and insisting he doesn’t want it.
The Daily Telegraph said one plan is for Mr Johnson to write a request for an extension alongside another letter outlining that the government doesn’t want one.
However legal experts have poured scorn on the idea, saying he would be breaking the law if he used the loophole.
Mr Johnson was warned at the weekend that he could be jailed if he doesn’t delay Brexit.
He is compelled to ask the EU for the deadline to be put back to January if MPs haven’t voted for a deal or approved no-deal by mid October under legislation pushed through the Commons by opposition MPs and Tory rebels.
The PM said last week he would rather be “dead in a ditch” than request an extension, suggesting he may try to find a way out by convincing Brussels to reject the request.
The EU has indicated it will not grant an extension “under current circumstances”, and France says it is sceptical about another delay.
Mr Johnson could accompany the Article 50 extension plea to Brussels with a letter stating his government does not want a delay past the current October 31 deadline.
Former Supreme Court justice Lord Sumption denied the move would be legal.
"No, of course it wouldn't," he told BBC Radio 4's Today programme on Monday.
"Not only has he got to send the letter, he's got to apply for an extension. To send the letter and then try to neutralise it seems to me, plainly, a breach of the Act.
"What you've got to realise is the courts are not very fond of loopholes."
Lord Falconer, a former justice secretary, reached the same conclusion.
The Labour peer tweeted: "Statutory Purpose of request letter is to get extension. To seek to destroy statutory purpose is to break law."
And the Criminal Bar Association (CBA) condemned suggestions the prime minister may be planning to ignore legislation designed to stop a no-deal Brexit.
CBA chair Caroline Goodwin said: “We cannot expect people not to rob, rape and murder when a government declares it may break the law. We cannot lay rape to the rule of law.”
The legislation that would extend the Brexit deadline to January 31 received Royal Assent on Monday meaning it is now officially law.
On Sunday, foreign secretary Dominic Raab said the government would "adhere to the law" but he said that ministers would "test to the limit what it does actually lawfully require".
He told Sky’s Sophy Ridge on Sunday: "We will look very carefully, legally, at what it requires and what it doesn't require.”
The prime minister has options to prevent the request for a delay to Brexit, which he said must happen by the October 31 deadline "do or die".
He could find a loophole, he could resign - a move he did not rule out when questioned last week - or find a way to force a general election.
In a meeting in Dublin with the Irish prime minister Leo Varadkar on Monday morning, Mr Johnson said a no-deal Brexit would be a “failure” and responsibility would lie with the British and Irish governments.
Mr Johnson said he believed it was possible to get a new agreement by October 18.
"I want to find a deal. I have looked carefully at no-deal,” he said.
“Yes, we could do it, the UK could certainly get through it, but be in no doubt that outcome would be a failure of statecraft for which we would all be responsible.
"I would overwhelmingly prefer to find an agreement. I do believe that a deal can be done by October 18 so let's do it together."
On Monday, Mr Johnson will ask MPs to grant him a general election for the second time.
But it is widely expected that he will again fail to get the required support from two-thirds of the Commons.
After the vote, Parliament is scheduled to be suspended until October 14 as ordered by the prime minister.
MPs will also debate on Monday a petition backed by 1.7 million people demanding Parliament must not be prorogued unless Article 50 is extended.
WILL THERE BE AN ELECTION?
The government has tabled a motion calling for an early poll, which will also be debated on Monday.
However with opposition parties agreeing not to support it, it is unlikely to garner the backing of the two-thirds of MPs needed for it to pass.