Boris Johnson and his allies have been warned by Downing Street against “traducing” the privileges committee.
The former prime minister quit parliament on Friday, accusing the committee - of “bias” and likening it to a “kangaroo court”.
He stood down after learning it would find him guilty of lying to parliament over partygate, recommending a sanction that could have triggered a by-election in his seat.
Rishi Sunak’s spokesperson said on Monday that people were “entitled to express opinions about the actions of government or committees”.
But he added: “What we would not want to see is people traducing the work of a legitimate committee which is carrying out work parliament has asked it to do.”
Asked about reported concerns over the security of the MPs on the committee, the spokesperson said: “I’ve only seen the reporting around that. I don’t know the facts. Clearly, any threats against any MPs are completely unacceptable.”
The committee is meeting today to finalise its report into whether Johnson misled MPs when he said no lockdown rules had been broken in Downing Street when he was PM.
According to The Sunday Telegraph, it might now also sanction Johnson’ allies who have criticised it in recent days.
Speaking to BBC Radio 4′s Today programme this morning, levelling up secretary Michael Gove also defended the integrity of the committee. But he refused to rebuke those who had attacked it.
“It is not my job or role to censor or police anyone’s views in a matter of public debate,” he said.
“I have respect for the work that they have done and I think that we need to respect again the integrity of the process and wait until the report is published before then debating its conclusions and the consequences.
“The second thing that I want to say is that I do deprecate the fact that they are now in a position where, as reported, they have to seek or have been granted additional security.”
The latest war of words between Johnson and Sunak also saw Nadine Dorries and Nigel Adams quit as MPs after being left off the list of new appointments to the House of Lords.
Both had been expected to be handed seats in the Lords in Johnson’s resignation honours list, but they were not included when it was published on Friday.
The House of Lords Appointments Commission (Holac) - which oversees the process - has said it did not approve eight names nominated by Johnson.
Downing Street said Sunak was “not involved” in any decisions about who was on Johnson’s list of peers.