Boris Johnson resigns as MP with immediate effect over Partygate report | Boris Johnson

Boris Johnson is standing down immediately as a Conservative MP after an investigation into the Partygate scandal found he misled parliament and recommended a lengthy suspension from the House of Commons.

The former prime minister angrily accused the investigation of trying to drive him out, and claimed there was a “witch-hunt under way, to take revenge for Brexit and ultimately to reverse the 2016 referendum result”.

In a bitter 1,000-word statement, he attacked Rishi Sunak’s government, blaming the current prime minister for rising taxes, not being Conservative enough and failing to make the most of Brexit.

Johnson hinted that he may try to make a return to politics, saying he was “very sad to be leaving parliament – at least for now”.

His departure from political life comes less than four years after he won an 80-seat political majority and nine months after he stood down as prime minister after a police fine for breaking his own Covid rules.

In his statement, Johnson hit out at political enemies for targeting him after he was shown the privileges committee findings against him earlier this week.

“It is very sad to be leaving parliament – at least for now – but above all I am bewildered and appalled that I can be forced out, anti-democratically, by a committee chaired and managed, by [the Labour MP] Harriet Harman, with such egregious bias,” he said.

“Their purpose from the beginning has been to find me guilty, regardless of the facts. This is the very definition of a kangaroo court.”

The resignation will trigger an immediate byelection in Johnson’s Uxbridge and South Ruislip constituency. It was the second in a day for Sunak after Nadine Dorries resigned as MP for Mid Bedfordshire after her inclusion on Johnson’s peerage list was blocked. Labour sources view both the seats as winnable.

Johnson’s dramatic move came on the day Sunak cleared a resignation honours list for him, including more than 40 peerages and other rewards, for some of his closest allies from the time of the Partygate scandal.

These include Martin Reynolds, who oversaw a Downing Street garden party during lockdown restrictions in 2020, and Jack Doyle, his former director of communications, who had discussed how to downplay the story.

Labour said the list amounted to “rewards for those who tried to cover up rule-breaking”, while the Lib Dems said it was “gongs for Johnson’s Partygate pals” and described it as “corruption pure and simple”.

Sunak had faced criticism for clearing the list while the privileges committee inquiry into Partygate was continuing, but Johnson’s resignation means their report will not have the same power as it would towards a sitting MP.

The committee of MPs, which has Tory, Labour and SNP members, is believed to have recommended his suspension for more than 10 days, which could have led to a recall petition and byelection in his constituency. The group is still likely to publish its report in the coming weeks.

Johnson accused his opponents of a “concerted attempt” to remove him from parliament. He said the privileges committee, led by Harman, had produced a report that was “riddled with inaccuracies and reeks of prejudice but under their absurd and unjust process I have no formal ability to challenge anything they say”. He claimed that he “did not lie, and I believe that in their hearts the committee know it”.

He blamed a “misplaced” faith in the impartiality of systems that led him to commission a report into the furore by Sue Gray, a senior civil servant who was subsequently chosen by Keir Starmer to be his new chief of staff. She will take up her role in the autumn.

The resignation statement also contained stinging criticisms of Sunak’s government and some fellow Conservative MPs.

“Of course, it suits the Labour party, the Liberal Democrats, and the SNP to do whatever they can to remove me from parliament,” he said. “Sadly, as we saw in July last year, there are currently some Tory MPs who share that view. I am not alone in thinking that there is a witch-hunt under way, to take revenge for Brexit and ultimately to reverse the 2016 referendum result.

“My removal is the necessary first step, and I believe there has been a concerted attempt to bring it about. I am afraid I no longer believe that it is any coincidence that Sue Gray – who investigated gatherings in No 10 – is now the chief of staff designate of the Labour leader.”

He added: “Our party needs urgently to recapture its sense of momentum and its belief in what this country can do.

“We need to show how we are making the most of Brexit and we need in the next months to be setting out a pro-growth and pro-investment agenda. We need to cut business and personal taxes – and not just as pre-election gimmicks – rather than endlessly putting them up.

“We must not be afraid to be a properly Conservative government. Why have we so passively abandoned the prospect of a free trade deal with the US? Why have we junked measures to help people into housing or to scrap EU directives or to promote animal welfare?”

There had been some speculation that Johnson could before the next election seek a safer parliamentary seat than his current one in Uxbridge, which is under threat from Labour. But Sunak and Conservative officials would have to approve his application as a candidate elsewhere.