Boris Johnson has finally succumb to the mounting pressure from his Government and resigned as Tory leader.

The Prime Minister’s resignation after haemorrhaging support among his ministers and MPs will fire the starting gun for a contest to replace him.

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.

Boris Johnson quits as UK Prime Minister

Boris Johnson statement

Boris Johnson was met by applause as he cmae outside confirming his resignation.

He said: "It is clearly now the will of the parliamentary conservative party that there should be a new leader of that party and so a new prime minister.

"I've agreed with Sir Graham Brady... that the process of choosing that new leader should begin now."

Mr Johnson confirmed he will remain in place "until a new leader is in place".

The Prime Minister revealed the reason why he tried so hard to cling on to power.

He said: "The reason I have fought so hard over the last few days to continue to deliver that mandate in person was not just because I wanted to do so, but because I felt it was my job, my duty, my obligation to you."

He continued: "I'm immensely proud of the achievements of this government in getting Brexit done, to settling our relations with the Continent... reclaiming the power for this country to make its own laws in Parliament.

"Getting this country through the pandemic, getting the fastest vaccine roll-out in Europe, the fastest exit from lockdown and in the last few months leading the West in standing up to Putin's aggression in Ukraine."

He then addressed the people in Ukraine, saying the UK will "continue to back their fight".

Boris Johnson confirmed his replacement will get his full backing and expressed is disappointment in leaving the "best job in the world".

"In the last few days I have tried to convince my colleagues it would be eccentric to change leader when we are delivering so much, when we have such a vast mandate and when we're only a couple of points behind in the polls."

He says he "regrets not to have been successful in those arguments." 

"It's painful not to be able to see through so many projects myself," Mr Johnson adds. "But as we've seen at Westminster the herd instinct is powerful.

"When the herd moves, it moves."

How Boris Johnson lost power as Prime Minister

The Prime Minister’s authority had already been damaged by a confidence vote which saw 41% of his own MPs withdraw their support in June.

The loss of crunch by-elections in Tiverton and Honiton and Wakefield later that month triggered the resignation of party chairman Oliver Dowden, while there is still lingering anger over coronavirus lockdown-busting parties in Downing Street.

Tory MPs are also uneasy about the Government’s high spending, high taxing approach as a result of the response to the pandemic.