Boris Johnson has made eleventh-hour representations to the privileges committee before it publishes a report which is expected to find that he deliberately misled parliament.
A spokesman for the inquiry said it was “dealing with” further submissions received from the former prime minister at 11.57pm on Monday.
It came as the panel of MPs examining claims that Mr Johnson lied to parliament over “partygate” met to conclude its investigation.
Their report was expected to be published as early as Wednesday after Mr Johnson quit as an MP, having received an advanced copy of its findings.
In an explosive 1,000-word statement he accused the committee, chaired by Labour’s Harriet Harman but with a Conservative majority, of “bias” and likened it to a “kangaroo court”.
It has been suggested that – before his shock resignation – the panel had been discussing a 20-day suspension, triggering a recall petition and potential by-election.
He cannot be suspended now he has resigned, but he could be refused a parliamentary pass offered to former MPs, a sanction imposed on former speaker John Bercow after a bullying report.
Despite the findings expected to be damaging, Mr Johnson has insisted “I’ll be back” – a reference to Arnold Schwarzenegger’s Terminator.
In the Daily Express, the former prime minister said “We must fully deliver on Brexit and on the 2019 manifesto. We must smash Labour at the next election.
“Nothing less than absolute victory and total Brexit will do – and as the great Arnold Schwarzenegger said, I’ll be back.”
The message echoed Mr Johnson’s sign-off during his final appearance at Prime Minister’s Questions last year, when he told MPs: “Hasta la vista, baby” – the catchphrase of Schwarzenegger’s cyborg character in the 1991 movie Terminator 2: Judgment Day.
That reference similarly left the door open for a possible comeback, but the former Uxbridge and South Ruislip MP remained on the back benches until quitting the Commons on Friday.