She is set to tell MPs there have been "robust views" on Brexit among cabinet members and is also expected to announce a replacement for Davis. Sources close to Jacob Rees-Mogg have always said that he supports the prime minister, and appears to be urging colleagues not to do so....
Conservative MP William Wragg, who campaigned for Brexit, said the resignation was "the right thing to do" while Tory MP Andrea Jenkyns, who quit a junior government role earlier this year to "fight for Brexit", said it was "fantastic news", adding: "Well done David Davis for having the principle and guts to resign".
May appointed Dominic Raab, who voted for Brexit in the 2016 referendum, as the new Brexit Secretary on Monday, just hours after Davis's resignation.
But Mr Davis, who signed up to the plan agreed by the cabinet at Chequers on Friday, has now quit.
Davis' resignation was followed by that of Exiting the EU Minister Steve Baker.
David Davis had already expressed unease over the compromise plan.
"May's Brexit means BRINO - "Brexit In Name Only" - a fake Brexit", said John Longworth, co-chairman of Leave Means Leave.
"It is now clearer than ever that Theresa May does not have the authority to negotiate for Britain or deliver a Brexit deal that protects jobs and the economy".
However, he also reportedly threatened to resign from the government on a number of occasions, most recently during talks to resolve a dispute with pro-EU Conservative lawmakers who wanted a greater say for parliament over the final Brexit deal.
Denying that he wanted to unseat the prime minister, he said he would now "argue for being as firm as possible".
May is due to address parliament on Monday to explain her plan for Britain to adopt European Union rules on goods after Brexit, amid anger from MPs in her own party who want a cleaner break and businesses who say it may still cause economic harm.
She said the government's Brexit plan was "far from perfect" but marked "grown-up steps". They have criticised the Chequers deal as offering a soft Brexit that betrays what they believe was a mandate for a clean break with the EU.
His resignation comes days after Theresa May secured the cabinet's backing for her Brexit plan despite claims from Brexiteers that it was too "soft". Conservative MPs have repeatedly told Business Insider that there is likely to be a challenge against her once Brexit negotiations conclude and Britain has left the European Union next March. If May fails to stabilise her party tonight then there is, for the first time, a real risk that Tory MPs will decide that enough is enough.