Rishi Sunak has dismissed claims that Nadhim Zahawi was unfairly treated after he was sacked for breaking the ministerial code in a row over his tax affairs, saying his government was committed to integrity. Senior MPs have privately suggested that Sunak’s action against Zahawi meant there could be no way back for the deputy prime minister, Dominic Raab – the subject of 24 bullying complaints. Sunak has delayed the appointment of a new Conservative party chair to replace Zahawi and could carry out a small wider reshuffle of his cabinet once he has made his decision whether or not to sack Raab, who is also the justice secretary. Zahawi has told allies he is considering publishing his own side of the story after he was sacked on Sunday morning just two hours after the conclusion of the investigation by Sunak’s new ethics adviser, Sir Laurie Magnus. Magnus concluded Zahawi had broken the rules by repeatedly failing to declare an HMRC investigation into his tax affairs where he was forced to pay a £5m settlement including a penalty. Zahawi is said to feel he was not given an opportunity to make his case, apart from one 30-minute meeting, and was unable to respond to the conclusions before they were made public. “He feels very hard done by,” one friend of Zahawi said. Another MP said Zahawi’s mistake was that he had seen it as an entirely personal affair. “Tax affairs are personal not public – and he was told this was ‘not deliberate’ so he felt he could weather this. But the scale of public opinion was enormous.” Another MP, who has worked closely with Zahawi, said he was a “top guy” and there was unease at the way he had been treated. But there have been no MPs prepared to go on the record to defend the former party chair. Zahawi also hit out at the way the media had pursued the story about his tax affairs – though No 10 has pointedly disagreed. Asked if Sunak agreed with Zahawi’s criticism of the media, the prime minister’s spokesperson said: “It is important to emphasise that, in a healthy democracy, the media plays a vitally important role in holding the government of the day to account. And I’m sure it will continue to do so.” The prime minister, answering questions after an NHS-themed address at Teesside University in Darlington, said he had acted “decisively” to dismiss Zahawi on Sunday. Magnus’s conclusions meant he was “able to make a very quick decision that it was no longer appropriate for Nadhim Zahawi to continue in government”, Sunak added. Sunak, who entered No 10 pledging to restore “integrity and accountability” in light of the Boris Johnson era, said his swift action on Magnus’s report demonstrated this was still his mission. “That should give you some confidence that these things matter to me, and that I will take whatever steps are necessary to restore the integrity back into politics, and you can have confidence that the process works.” That emphasis by Sunak on his determination to act differently – despite being criticised for the delay in sacking Zahawi – has all but confirmed many MPs’ views that Raab will not be able to avoid the same fate. That would mean Sunak having lost three cabinet ministers since he became prime minister in October, following Gavin Williamson’s resignation in November. “Dominic has to be toast,” said one senior ally of Sunak. “There is no escaping the fact that with so many complaints that it is highly unlikely he will be exonerated.” The justice secretary has strongly denied bullying staff. His conduct is being investigated separately by a senior employment barrister, Adam Tolley KC. Sunak may take a week to appoint Zahawi’s replacement. The leader of the House of Commons, Penny Mordaunt, has been tipped for the role but there is some scepticism Sunak would be comfortable giving a previously powerful leadership rival control of the party machinery. “He wants someone in there who is a close ally,” one MP said. Oliver Dowden, who chaired Sunak’s leadership campaign, is also a possibility. “He knows the donors, he can do the attack dog role, he can do the strategy,” one former minister said. Dowden may not be keen to return to the role, however, having previously resigned after the May 2022 elections – though the decision was partly due to the conduct of Johnson, who was prime minister at the time. The role of party chair is likely to be increasingly crucial over the coming months – when MPs will start to take more of an interest in currying favour with the party in order to gain resources to fight their seats, rather than jostling for positions in government, which is a scenario where the chief whip is the more powerful. The former Tory leader William Hague has said he will not be taking the role, despite some speculation. Lord Hague, who previously represented Sunak’s Richmond constituency, addressed cabinet ministers at their away day last week. “Since I’ve seen reports of people placing bets on me being the new party chairman, please be aware that I will absolutely not be returning to politics in any shape or form, including that one,” he tweeted.