Mrs May said she wanted to recognise the work of the former Brexit Secretary on steering through some of the "most important legislation for generations".
"What the Prime Minister needs to do is to give up on the Chequers proposal. which does not actually deliver Brexit", he told LBC Radio.
'As I said then, the Government now has a song to sing.
On Monday, high-profile Brexiteer and Conservative MP Johnson announced he was resigning from the Cabinet, following the agreement of a Brexit proposal that would see the United Kingdom retain close links to the European Union after exiting the organisation. Since I can not in all conscience champion these proposals, I have sadly concluded that I must go.
Two senior sources confirmed Mr Davis' departure from the Cabinet.
Theresa May's government is in crisis. They have organised a highly successful Commonwealth summit and secured record global support for this Government's campaign for 12 years of quality education for every girl, and much more besides.
He said: "My principal job is to stand four square behind the Prime Minister so that we can get through an agreement with the European Union based on what was agreed by the Cabinet last week at Chequers".
Mr Hunt is replaced at Health and Social Care by Culture Secretary Matt Hancock, who will in turn be succeeded by Attorney General Jeremy Wright.
"In his resignation letter, Davis said the "'common rule book policy hands control of large swathes of our economy to the European Union and is certainly not returning control of our laws in any real sense".
"I had to resign because this was central to my job and if we continue with this policy and I was still there, I'd have to present it to parliament and the House of Commons, I'd have to present it in Europe. Since I can not in all conscience champion these proposals, I have sadly concluded that I must go". It is also clear that by surrendering control over our rulebook for goods and agrifoods (and much else besides) we will make it much more hard to do free trade deals.
Mr Davis denied coordinating his resignation with Mr Johnson.
"I don't think it's a survival issue at all".
Jeremy Hunt visited the Foreign Office last night.
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