Dominic Raab has said he does not see how anybody could “reconcile” supporting the return of Boris Johnson to Downing Street while he is still being investigated for Partygate as he threw his weight behind Rishi Sunak. The Conservative MP, who was deputy prime minister under Johnson, said although he believed a return to frontline politics was possible for the former prime minister, he did not back it happening while he was subject to an ongoing inquiry. “Whether you’re an arch Boris fan or an arch Boris critic I don’t see how you can reconcile returning to frontline politics with that committee looming and hanging over and oral testimony being heard,” he told BBC Radio 4’s Today programme on Saturday morning, as Sunak approached 100 public nominations from Tory MPs. As well as oral testimony from No 10 staff, he said Johnson would also have to give evidence, adding: “And I just can’t see in practice how a new prime minister in office, latest next Friday, could give the country the attention, the focus that it needs and at the same time be giving testimony and be answering all of those questions.” While he said he “stood by Boris” and had “a lot of respect for him”, Raab said the country “cannot go backwards”. He added: “We cannot have another episode of the Groundhog Day, of the soap opera of Partygate, we must get the country and the government moving forward.” Asked whether Sunak and Johnson had any plans to meet, he said he did not know but that he was “sure he’s open to doing so”. Sunak, he said, had “consistently been clear” about the route to financial stability for the UK: bringing down inflation, lowering mortgage interest rates and restoring confidence in the economy for businesses and workers. He added: “And I think he is the best placed leader to bring the Conservative family together, to bring a government of all the talents so that we can be focused relentlessly, consistently, from the get-go on delivering for the British people on the cost of living but also on the NHS, schools, crime and immigration.” Asked whether the Conservative party owed the country an apology, he admitted that the UK faced “massive challenges” and that the party had a “responsibility in the national interest to address and restore the stability that has been lacking”. He added: “But these are difficult times and we need a leader that can rise to that challenge and that’s why I’m backing Rishi.” In another media appearance soon after, he told BBC Breakfast that Sunak had “the broadest appeal”. “He can restore trust. I think he is best placed to restore that confidence that we sorely need,” he added. According to the latest Guardian count, at 10am on Saturday, Sunak leads the contest with 90 public nominations – almost double Johnson’s 48. Penny Mordaunt trailed with 22. In order for candidates to make it to the first round of voting on Monday, they must meet the threshold of 100 nominations. Chris Bryant, the Labour MP for Rhondda and chair of the Commons committee on standards, said the public wanted a general election to “press the reset button”. Bryant was previously part of the cross-party privileges committee investigating whether Johnson deliberately misled parliament about the parties held in No 10 but withdrew after publicly condemning his behaviour. Asked about the former prime minister returning to the role on the Today programme, he said: “He’s disgraced. I mean, look, I’m a Labour MP, I don’t fancy any of the three of them. I think we’ve got to a stage now where the people of this country think the only way you can press the reset button is to have a general election.” If Johnson was again elected leader, he predicted that multiple Conservative MPs would “either cross the floor or abandon support for him”. He added: “His biggest problem is, he will be spending probably the first two months of his second premiership entirely focused on the privileges inquiry and may, at the end of it, be found to have been in contempt of parliament, suspended from the House of Commons and potentially facing a byelection in a seat which he would lose.”