But as Foreign Secretary in May's government, he was prone to gaffes and criticized for not being on top of his brief.
Labour MP Chuka Umunna, a strong supported of the campaign, said: "Brexit is turning into an unholy and undeliverable mess".
The prime minister was given backing by senior Tory figures from the Brexit and Remain sides as Downing Street tried to contain the rebellion by up to 80 members of the European Research Group of hard Brexiteers who attended last night's meeting.
Mrs May is expected to use a Commons statement to tell MPs that the strategy agreed on at Chequers is the "right Brexit" for Britain.
"I doubt the prime minister will survive long", a member of the Conservative Party's pro-Brexit wing told Business Insider yesterday.
"The government now has a song to sing".
Death Toll Exceeds 100 After Heavy Rainfall Slams Japan
A man and his wife protect their home from water with sand bags in Saka, Hiroshima prefecture. "I've lived here for 40 years". Local government officials said pumping trucks were being deployed to help restore access to some of the worst-hit areas.
"The trouble is that I have practised the words over the weekend and I find they stick in the throat".
It said May now faces "the spectre of a leadership challenge", but it was "possible that after a period of resignations and political blood-letting, the Conservative Party will fall behind the prime minister".
Mrs May has now appointed Dominic Raab and Jeremy Hunt to replace Mr Davis and Mr Johnson.
Davis did not urge other ministers to resign, saying he was in a unique position because the Brexit secretary's job is to sell the government's policy.
The Guardian newspaper quoted an unnamed Conservative MP saying the resignations would continue in protest against her plan to keep strong economic ties with the European Union - dubbed the Chequers plan after her country retreat where it was agreed last week.
The "common rulebook" plan "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", he wrote to Mrs May.
Queen marks 100 years of RAF ahead of flypast
The Queen looked well after skipping Prince Louis's Christening on Monday, following a busy week in Scotland last week. Kate Middleton and Prince William at Prince Louis' christening service.
Boris Johnson's resignation a selfish act, says Guto Bebb
May was asked by an opposition lawmaker Monday whether she would contest a vote of confidence if one came rather than resign. Top Brexiteer Michael Gove, an ally of Mr Davis , Mr Johnson and also Mrs May, said everybody was "in very good spirits".
Profiles: Matt Hancock and Jeremy Wright
Many Brexit campaigners in her Conservative Party say she has betrayed her promise to pursue a clean break with the EU. Matt Hancock , Secretary of State for Digital, Culture, Media and Sport has replaced Jeremy Hunt as Health Secretary.
PSG make world record bid for former Liverpool ace, Coutinho
The pair clashed last season over penalty taking duties and it is believed that the 26-year-old would rather see Cavani leave. PSG remain at the centre of an investigation by UEFA after they spent nearly £400m on Neymar and Kylian Mbappe last summer.
George Clooney injured in scooter accident in Italy
The Hollywood actor collided with a Mercedes auto on Tuesday morning while in Puntaldia, Sardinia, on the way to a TV set. George Clooney is interviewed at the premiere for "Suburbicon" in Los Angeles, California last October.
England fans celebrate World Cup win over Sweden at IKEA
The Spurs right-back has been one of the key men in the squad as Gareth Southgate's side have reached the World Cup semi-final. The Euro '96 anthem managed to topple Drake from the top spot, clocking up over one million streams in just one day.
Trump says Putin meeting may be 'easiest'
But his trip to Brussels may end up being less controversial, said Dan Michaels, the Wall Street Journal Brussels bureau chief. Meanwhile, Mr Trump will be largely kept away from central London.
It’s official: Lakers announce LeBron James has signed
It's a big day for the Los Angeles Lakers as LeBron James signed his 4-year $154-million contract with the purple and gold. LeBron is a Laker . "It's a huge step closer to returning the Lakers to the playoffs and to the NBA Finals".