Boris Johnson is quitting as Tory leader after ministers and MPs made clear his position was untenable.

He will remain as Prime Minister until a successor is in place, expected to be by the time of the Conservative Party conference in October.

A No 10 source said Mr Johnson spoke to Sir Graham Brady, chairman of the Conservative 1922 Committee, to inform him of his decision.

“The Prime Minister has spoken to Graham Brady and agreed to stand down in time for a new leader to be in place by the conference in October,” a No 10 source said.

Steve Brine MP yesterday re-submitted his letter of no confidence in Boris Johnson after the resignations of Rishi Sunak and Sajid Javid on Tuesday evening sparked a mass exodus.

He said there were some "powerful new voices" on the backbenches urging the parliamentary party to "turn the page".

Reacting to the news this morning, Mr Brine said: “My constituents know I will not exactly be sorry to see Boris Johnson go and, indeed, I made it clear a long time ago I didn’t have confidence in him to continue as Prime Minister.

“I realise however, not everyone shares that view, and indeed for some locally this is the worst possible news for their plans, but as a country and a party we need to turn the page. We face so many challenges at this time, and have a manifesto to fulfil, which deserve the full attention of Government.

“I will do all I can to help a smooth transition in the coming months but don’t think it’s accepted wisdom Boris automatically stays in No.10 until the Autumn. That is for the party to discuss next week. Either way, I wish the outgoing PM best wishes for the future with his young family.”

Member of Parliament for Meon Valley, Flick Drummond, said it is "disappointing" to see Mr Johnson go in these circumstances, but believes the time was right for him to step aside.

"I am pleased Boris Johnson is to resign," she said. "Yesterday, I told the Chief Whip I had no confidence in the Prime Minister and I asked him to convey my view that he should resign.

"I will stay on in my PPS role at the Department for Work and Pensions. I work for a wonderful secretary of state and I feel helping to ensure this important department carries on its good work must come first. DWP is at the forefront of the government’s response to the cost-of-living crisis.

"We should be proud of what the government has achieved so far. We have got Brexit done, weathered the pandemic, given international leadership to thwart Russian aggression and we have delivered on our manifesto.

"It is disappointing the Prime Minister has had to go in these circumstances but it is right he has done so."

Caroline Nokes MP, who was part of the Liaison Committee which grilled Mr Johnson yesterday afternoon, said if Mr Johnson "had not recognised the need to resign by the end of the day" she would follow suit. Ms Nokes has been contacted for comment.

Danny Chambers, Lib Dem candidate for Winchester and Chandler's Ford said: “It has always been clear that Boris Johnson is unfit to lead our country. The public won't forgive the Conservatives for propping him up for so long.

“Conservatives have spent months defending him instead of focusing on the cost-of-living crisis & the crisis in our NHS.

“We need MPs and politicians who uphold standards in public life. If I lied and broke the rules as a veterinary surgeon I would get struck off, and rightly so.

“We must all vote for change at the next opportunity. In Winchester and Chandler’s Ford, that means voting for me and the Liberal Democrats.”

Meanwhile, the general reaction was one of relief from those in Winchester this morning, although some were worried about what is to come.

Mary Brown, retired from Chandlers Ford, said: "I'm really glad but I think we need to get rid of his whole cabinet because they're all tainted. The deceit in this Government is appalling."

Hampshire Chronicle: Mary BrownMary Brown

Michael Williams, 75, from Alton, said: "It's a shame. I had high hopes for him but it has all fallen to bits. Let's hope they put someone good in his place."

Katie Hardy, 33, from Winchester said: "It's about time. He lost the support of the public when he broke the rules during Covid. I lost my nan during that time and that was really hard, and even more so to see that Boris had been partying. So, I'm glad."

Caroline and Tony Roberts from Highcliffe were strong supporters of his resignation. Caroline said: "Great. This is the best thing."

Hampshire Chronicle: Caroline and Tony RobertsCaroline and Tony Roberts

Her husband Tony was less positive, he said: "I've got mixed emotions as it's all quite unpredictable. Just because he's resigning it doesn't mean he's leaving."

Britain's Attorney General, Fareham MP Suella Braverman, had urged Mr Johnson to stand down as well as signalling her intention to stand in a future leadership contest.

Desmond Swayne, Tory MP for New Forest West, tweeted his support for Ms Braverman just moments after the announcement that Mr Johnson is set to resign as prime minister.

He said: "I'm backing Suella."

Mr Johnson will make a statement to the country later today confirming the decision.

The resignation comes after the Prime Minister haemorrhaged support among his ministers and MPs.

More than 50 MPs have resigned from government or party roles since Tuesday night, when the mass exodus was triggered by the resignations of Rishi Sunak and Sajid Javid from the Cabinet.

The Prime Minister had sought to defy his critics and carry on in office, despite warnings from Cabinet colleagues that this was not sustainable.

But resignations continued and Chancellor Nadhim Zahawi – who was only appointed to the role on Tuesday – went public with his call for the Prime Minister to quit.