Ian Blackford was ordered to leave the House of Commons after accusing Boris Johnson of having “wilfully misled” MPs over the Downing Street party allegations.

The SNP Westminster leader was repeatedly asked by Speaker Sir Lindsay Hoyle to withdraw the claim, as it is considered against parliamentary etiquette to make such an assertion.

Mr Blackford replied that the Prime Minister “may have inadvertently misled the House”, but Sir Lindsay asked: “To help me help the House, you’ve withdrawn your earlier comment and replaced it with inadvertently?”

Mr Blackford replied: “It’s not my fault if the Prime Minister can’t be trusted to tell the truth.”

Amid raucous shouting from the Tory benches, the Speaker said: “Under the power given to me by standing order number 43 I order the honourable member to withdraw immediately from the House.”

Mr Blackford walked out of the chamber before the Speaker had finished, with Sir Lindsay noting: “It’s all right, we don’t need to bother.”

Earlier, Mr Blackford had said: “So here we have it. The long-awaited Sue Gray report, what a farce.

“It was carefully engineered to be a fact-finding exercise, with no conclusions. Now we find it’s a fact-finding exercise with no facts.

“So let’s talk facts. The Prime Minister has told the House that all guidance was completely followed, there was no party, Covid rules were followed and that ‘I believed it was a work event’.

“Nobody, nobody believed it then. And nobody, nobody believes you now, Prime Minister. That is the crux, no ifs, no buts, he has wilfully misled Parliament.”