In a live TV speech from the stairs to 10 Downing street, Johnson told at 13:30 on Thursday Swedish time that he is resigning as party leader.
However, he will continue to act as administrative prime minister until a new leader of the Tory party is appointed.
Shortly after 10 o'clock, the BBC and several other British media announced that Johnson would resign, and the prelude has been difficult to avoid in recent days.
The Prime Minister's career has been followed by scandals, not least the so-called Partygate, where he was accused of partying in the Government Offices, which is also his residence, during a time when the country was under strict lockdown due to the corona pandemic.
Large number of dropouts
But the protests reached their climax this week when ministers began to leave their posts in dissatisfaction with Johnson's leadership.
The defection began on Tuesday, when Finance Minister Rishi Sunak and Health Minister Sajid Javid left in protest against a Conservative MP being offered a top job in the government despite allegations of sexual harassment.
Since then, the defections have hailed, and on Thursday as many as 60 people left their posts.
Continues as Prime Minister
In his six-minute speech, he lamented that he is now leaving "the world's best job," but also said that he will continue as administrative prime minister, the premise "administrative" means that his ability to introduce political change will be limited.
- Together with a replacement cabinet, I will remain until we have a new leader.
At 20:30 Swedish time, according to the BBC, Downing Street announced ten of the new ministers who will be part of the compensation cabinet.