The rising star of the Conservative Party has long called for a tough stance towards Brussels as the UK makes its way out of the EU.
Shortly after the Prime Minister’s deal fell apart at the hands of her Commons allies the DUP last week, Mr Rees-Mogg advised Mrs May to apply “a fresh coat of paint to her red lines”.
Now he has hit out at the deal sealed to progress onto the second round of talks – arguing Britain needs to be “robust” if it wants to stand up to Brussels.
The Brexiteer hit out at the possibility the EU “acquis” – the sum of all EU law and legislation – could still apply to the UK after Brexit, as well as the rule of the ECJ and free movement.
He said: “As usual the EU has set out a hard nosed negotiating stance, we must be equally robust.
“If the acquis, the ECJ and free movement remain we would not be in an implementation period but would still be de facto in the EU.
“I assume that Her Majesty’s Government will make its own proposals and not roll over in the way it did at the beginning of the process.”
It comes after Mr Rees-Mogg was revealed to be Conservative Party members’ top choice for promotion to Theresa May’s Cabinet after winning a landslide victory in a recent poll.
The MP for North East Somerset got more votes in the survey than the five people behind him put together, the Conservative Home poll revealed.
However, when Mr Rees-Mogg was rumoured to be in “line for ministerial” work in September, he dismissed the notion and said: “This isn’t going to happen. I’m very happy serving the people of North East Somerset.
“That’s my role, that’s what I enjoy doing. I think to start putting oneself forward is a great mistake.
“Heaven knows next you’ll be offering me the Papacy.”
Mr Rees-Mogg has been gaining traction among grassroots Tories after an online campaign called “Moggmentum” was started by young party members in the summer.
The results of the recent poll were published by Conservative Home, collating the opinions of “fewer than 1,000 people”.
MP for Braintree James Cleverly was second, MP for Plymouth Moor View Jonny Mercer was third, MP for Wokingham John Redwood was fourth and MP for Tonbridge and Malling Tom Tugendhat was fifth.