Boris Johnson’s legal team has handed over to MPs his defence dossier seeking to rebut allegations he lied to Parliament with his partygate denials.
Sources close to the former prime minister urged the Privileges Committee to make the evidence public “as soon as possible” ahead of his televised questioning on Wednesday.
Mr Johnson’s written evidence is key to his political future because a finding that he committed a contempt of Parliament could lead to his suspension and a possible by-election.
An ally of Mr Johnson said: “Boris’s formal submission has been made to the committee today, as planned.
“The committee control the timing of publication. We encourage them to publish it as soon as possible.”
The defence was expected to take the form of a lengthy submission from Mr Johnson’s barrister Lord Pannick KC.
Meanwhile, Downing Street has warned his supporters against interfering in the inquiry.
Rishi Sunak’s official spokesman defended the Privileges Committee investigation as friends of the former prime minister sought to portray it as a “witch hunt”.
Conor Burns, a Tory MP who served as a minister in Mr Johnson’s government, has raised questions about the committee’s chairwoman, the Labour grandee Harriet Harman.
And Tory peer Lord Greenhalgh backed a campaign for the four Conservative MPs on the Tory-majority committee to pull out of the “kangaroo court”.
The long-standing ally of Mr Johnson, who served under him at Westminster and City Hall, told Times Radio: “I’m concerned that it will be a witch hunt.”
The Prime Minister’s official spokesman responded by saying Mr Sunak “firmly believes it’s a matter for Parliament”, adding: “Parliament empowered the committee to carry out its work.”
He endorsed Commons Leader Penny Mordaunt’s warning that “a very dim view will be taken” of anyone who “tries to prevent them from carrying out this serious work”.
She also said the committee must be able to “work without fear or favour”.
Downing Street was also forced to deny it had delayed key announcements because of the distraction that will be caused by Mr Johnson’s inquiry appearance.
“It’s wrong to suggest Government business changes as a result of this committee hearing,” the spokesman said.
The hearing clashes with a key vote on Mr Sunak’s new Brexit deal for Northern Ireland, which Democratic Unionist Party MPs plan to oppose.
An estimated £220,000 of taxpayers’ money has been allocated for Mr Johnson’s legal bills.
If the committee rules that he did mislead the House, they will consider whether it was “reckless or intentional” and amounted to a contempt of Parliament.
An interim report by the committee earlier this month said evidence strongly suggested breaches of coronavirus rules would have been “obvious” to the then-prime minister.
But Mr Johnson claimed it was “clear” that he had not committed a contempt of Parliament, arguing there is “no evidence in the report that I knowingly or recklessly misled Parliament” or failed to update it in a timely manner.
Mr Johnson has also sought to cast doubt on the findings of Sue Gray’s report on partygate, after she quit the civil service to take up a role in Labour leader Sir Keir Starmer’s office.
“Boris Johnson contests that but it seems to me the person who is chairing this committee has predetermined it and that causes me a degree of anxiety for Parliament’s reputation in handling this with integrity.”
The Privileges Committee is examining evidence around at least four occasions when Mr Johnson may have misled MPs with his assurances to the Commons that lockdown rules were followed.
He is expected to highlight previously undisclosed WhatsApp messages from senior civil servants and members of his No 10 team showing he had relied on their advice when he made his statements to Parliament.
He will also publish messages which show other senior figures in Downing Street believed the gatherings were covered by the “workplace exemption” in the lockdown rules.
The committee will publish its findings on whether Mr Johnson committed a contempt of Parliament and make a recommendation on any punishment but the ultimate decision will fall to the full House of Commons.
Mr Sunak has said he will not seek to influence MPs on the committee and is expected to grant a free vote in the Commons on any sanction that may be recommended.
A suspension of 10 sitting days or more for Mr Johnson could ultimately trigger a by-election in his Uxbridge and South Ruislip seat, which he held with a majority of 7,210 in 2019.