Mr Johnson wrote in the Daily Telegraph that the Chequers plan would be a “disaster” for Britain.
As a response to Johnson’s criticism, Downing Street has said that the prime minister is indeed offering “a serious plan” and “serious leadership”.
Additionally, Downing Street also stated that the Chequers plan could potentially win the support of the House of Commons as it was deliverable.
The prime minister’s spokesperson stated: “There’s no new ideas in this article to respond to”.
The ex foreign secretary has said that Mrs. May’s plan would be beneficial for the EU rather than the UK.
He resigned as foreign secretary in July as an act of protest against the Chequers deal which informed how the UK would negotiate with Brussels about Brexit. This deal was created at the prime minister’s country residence by herself and her cabinet of ministers in July this year.
The plan has received a great deal of criticism namely from Tory MPs and the EU chief negotiator, Michel Barnier who “strongly opposed” it.
Many have argued that May’s plan would mean that the UK would still be tied to the EU by following its rules.
The UK is due to leave the EU on 29 March 2019.
Once the UK and the EU have come to an agreement on a Brexit plan, then MPs would have to accept it.
Johnson compared talks between new Brexit secretary Dominic Raab and Michel Barnier to a wrestling match.
“The whole thing is about as pre-ordained as a bout between Giant Haystacks and Big daddy; and in this case, I am afraid, the inevitable outcome is a victory for the EU, with the UK lying flat on the canvas and 12 stars circling symbolically over our semi-conscious head,” said Johnson.
“The UK has agreed to hand over £400 billion of taxpayers’ money for two-thirds of diddly squat.”
He believes that Chequers rids the UK of “most of the advantages of Brexit”.