Therefore, in the interests of our country and the future of the Conservative Party, I feel the time has come for a new leader and so I am writing this letter to inform you that I have no confidence in the Prime Minister.
May named one of her most loyal ministers, Jeremy Hunt, to replace Johnson in the job of Britain's top diplomat.
And he warned: "A government that depends upon the opposition to get its business through is like the gingerbread man on the back of the fox crossing the river".
After a dramatic day of twists and turns in Westminster, the prime minister addressed Conservative MPs for an hour, issuing a stark warning that divided parties lose elections and telling her party that "to lead is to decide". The British government is due to publish a detailed version of the plans on Thursday.
The US president said it was "up to the people" whether or not Theresa May remained as prime minister.
"The general direction of policy will leave us in at best a weak negotiating position, and possibly an inescapable one", he said.
Unnamed Brexiteers were quoted in the press as saying the PM should brace herself for "guerrilla war" to kill off her deal, with Eurosceptic Tories withholding their support in the Commons.
And senior backbencher Bernard Jenkin said there had been a "massive haemorrhage of trust" in Mrs May.
"He said it here in Dublin past year, that he didn't want a Norway type agreement because he felt that Britain would be rule takers - and that's the fundamental difficulty, Brexiteers are failing to grasp that when you enter an agreement with 27 other countries you agree to share a sovereignty".
"It takes 48 Conservative members out of a total of 60 to trigger a leadership challenge; however, we are unlikely to see the challenge happen because there is not yet the belief that they have the numbers to effectively oust Theresa May", Hoez added. It is an indulgence not a policy'.
Iran to continue oil exports despite USA disruptive measures: Zanganeh
Even if the Europeans cave in to United States demands, the world has changed a great deal since the pre-Iran deal era. Now, President Trump is threatening sanctions against any country that continues to do business with Iran.
Mr Bradley said in his resignation letter that the Chequers plan would damage the UK's opportunities to develop global trade and be "an outward-looking nation in control of our own destiny" following Brexit.
Brexiteer Andrea Jenkyns, a vocal critic of Mrs May, said it was time to "put country first".
"What the prime minister is proposing is a way in which we can ensure we don't have ... friction with our trade with the European Union ... and here is a practical way in which we can do that", Gauke said.
But leading pro-Brexit lawmaker Jacob Rees-Mogg said he didn't think she would face a leadership challenge.
The ex Foreign Secretary said Mrs May was putting Britain on a track to having "the status of a colony".
"They´ll keep going, one by one, until she either junks Chequers or goes", the MP was quoted as saying.
"I've listened to every possible idea and every possible version of Brexit".
She said: 'I am sorry - and a little surprised - to receive it [resignation letter] after the productive discussions we had at Chequers on Friday, and the comprehensive and detailed proposal which we agreed as a Cabinet'.