Boris Johnson has accused the Privileges Committee of making “Mystic Meg” claims and reaching a “deranged conclusion”, in a blistering response to its report.

The former prime minister released a 1,678-word statement lashing out at the Tory-majority group of MPs he has repeatedly sought to disparage.

It came after they found he committed “repeated contempts” of Parliament by deliberately misleading the Commons with his partygate denials before being complicit in a campaign of abuse and intimidation of the committee.

But Mr Johnson, who previously branded it a “kangaroo court”, continued his attacks on the panel and its findings, which he described as “a load of complete tripe”.

He repeatedly targeted committee chairwoman Harriet Harman, accusing her of holding “prejudicial views”, as well as the panel’s most senior Conservative member, Sir Bernard Jenkin.

One of the committee’s arguments was “so threadbare” that it belonged “in one of Bernard Jenkin’s nudist colonies”, Mr Johnson wrote in typically colourful language.

The ex-premier called the committee “beneath contempt” and claimed its 14-month investigation had delivered “what is intended to be the final knife-thrust in a protracted political assassination”.

On its conclusion that he deliberately misled the House, Mr Johnson said: “This is rubbish. It is a lie.”

He went through the committee’s findings one by one, repeating his lines of defence, including that he believed farewell events held during lockdown restrictions “were reasonably necessary for work purposes”.

“For the committee now to say that all such events – ‘thank yous’ and birthdays – were intrinsically illegal is ludicrous,” he wrote.

He also once again tore into Sir Bernard, who he has already urged to resign following a report that the MP went to a drinks party in Parliament while Covid restrictions were in place in 2020.

“The hypocrisy is rank. Like Harriet Harman, he should have recused himself from the inquiry, since he is plainly conflicted.”

Mr Johnson took particular offence at the panel’s findings about his knowledge of a Christmas cheese and wine gathering in December 2020.

“Perhaps the craziest assertion of all is the committee’s Mystic Meg claim that I saw the December 18 event with my own eyes,” he said.

“How on earth do these clairvoyants know exactly what was going on at 21.58?”

“How do they know what I saw? What retinal impressions have they somehow discovered, that are completely unavailable to me?

“It is a measure of the committee’s desperation that they are trying incompetently and absurdly to tie me to an illicit event – with an argument so threadbare that it belongs in one of Bernard Jenkin’s nudist colonies.”