Cabinet minister Grant Shapps has insisted Rishi Sunak did not intervene in Boris Johnson’s honours list as he claimed the world had “moved on” following his dramatic exit.

Mr Shapps, the energy secretary, said there were now “different challenges to face” and that Downing Street was “under new management”.

“We’ve got new management in Number 10, getting on with the job and getting on with the priorities of this country,” he told Sky’s Sophy Ridge on Sunday programme.

Mr Shapps spoke following Mr Johnson’s shock decision to resign as the MP for Uxbridge and South Ruislip on Friday, triggering a by-election in his constituency – a key target for Labour.

The former prime minister announced his decision after receiving the privileges committee report into whether he lied to MPs over partygate – something he branded a “kangaroo court” and “witch hunt”.

It came just hours after his resignation honours list had been published, with the names key allies Nadine Dorries, Sir Alok Sharma and Nigel Adams absent.

In a move that will create a headache for Mr Sunak, Ms Dorries, the former culture secretary, and Mr Adams, a former minister, both announced they would stand down from their seats, creating a hattrick of by-elections at a time when the polls are faring badly for the Tories.

Over the weekend there were reports in the Sunday Times that Mr Johnson believed Mr Sunak had broken a promise to wave through the entire list of honours – a charge Downing Street has denied.

But Mr Shapps insisted Mr Sunak made no changes to the list “at all”.

Asked whether he thinks Mr Johnson wasn’t fully across the process, he said the former prime minister “occasionally… wouldn’t be all over the details”.

“I don’t know whether that’s what happened in this particular case.”

In an excoriating statement announcing his resignation, the former prime minister said a letter from the privileges committee made clear “that they are determined to use the proceedings against me to drive me out of parliament”.

Mr Shapps has said he did not agree with Mr Johnson’s assessment that the committee’s partygate probe was a “witch hunt” and an attempt to reverse Brexit.

“I think far from wanting to undo (Brexit), I think we’re in a phase now of using the many benefits of having that extra flexibility,” he said.

“So, no, I don’t think that is the case.”

He went on to say that he had not seen the privileges committee report, so did not know what the former prime minister was “getting at” with his complaints of a “kangaroo court”.

“What I do believe is that it is very important to elect committees, let them get on with their work,” he said.

“I think the point of a member being sent details in advance, as has happened with Boris, is it gives someone the opportunity to comment on it and say, ‘No, this is an inaccuracy’ or what have you, and challenge it before it is published.

“Do I think that the process is proper? Well, that is a decision for Parliament and not the Government, but Parliament and MPs decide themselves, and this is the process that MPs have collectively decided should be in place in situations like this.”