Labour leader Keir Starmer criticised the prime minister's failure to sack Mr Zahawi over tax issues, ITV News' Amy Lewis reports
Rishi Sunak has defended his handling of Nadhim Zahawi's tax row as pressure grows on the Tory chairman to stand down.
Mr Sunak was asked whether he thought the role of prime minister was "too big" for him as he was quizzed at PMQs about failings in the probation services and Mr Zahawi's tax affairs.
The prime minister suggested that while it would have been "politically expedient" to sack Mr Zahawi, "due process" means the investigation into his tax affairs should be allowed to reach its conclusion.
The Labour leader told MPs that it was "fairly obvious that someone who seeks to avoid tax can’t also be in charge of tax".
"Yet for some reason the prime minister can’t bring himself to say that or even acknowledge the question," he said, alluding to Mr Sunak's wife's former non-dom status.
But Mr Sunak said Mr Zahawi had not been appointed by him and he had launched an investigation after "new information" came to light.
"I am pleased to make my position on this matter completely clear to the House. The issues in question occurred before I was prime minister," Mr Sunak said.
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"With regard to the appointment of the minister without portfolio, the usual appointments process was followed, no issues were raised with me when he was appointed to his current role, and since I commented on this matter last week, more information has come forward," Mr Sunak told the House.
Later in the day, Downing Street bowed to pressure to say Mr Sunak has never paid a tax penalty.
The prime minister’s press secretary initially insisted Mr Sunak’s tax affairs were "confidential", even as he prepared to publish his tax return in an attempt at transparency.
Keir Starmer had said the prime minister's failure to sack Mr Zahawi showed "how hopelessly weak he is".
"He can’t say when ambulances will get to heart attack victims again. He can’t say when the prisons system will keep streets safe again. He can’t even deal with tax avoiders in his own Cabinet.
"Is he starting to wonder if this job is just too big for him?"
In his final remarks to Sir Keir, Mr Sunak said: "The difference between him and me is I stand by my values and my principles even when it is difficult.
"When I disagreed fundamentally with the previous prime minister I resigned from the government.
"But for four long years he sat next to the member for Islington North [Jeremy Corbyn] - when antisemitism ran rife, when his predecessor sided with our opponents.
"That’s what’s weak, Mr Speaker. He has no principles and just petty politics."
The Labour leader had begun by asking the prime minister if he accepted the findings of a report that highlighted the failings that allowed Jordan McSweeney to kill Zara Aleena.
Speaking at Prime Minister's Questions, Sir Keir Starmer told the Commons: "Zara Aleena was walking home from a night out with her friends when she was savagely attacked, assaulted, and beaten to death. Zara was a brilliant young woman, a trainee lawyer with a bright future."
Sir Keir said her killer was "not fit to walk the same streets", adding: "But that's precisely the problem. He was free to walk the same streets.
"The inspectorate report into her case says that opportunities were missed by the probation service that could have prevented this attack and saved her life. Does the prime minister accept those findings?"
Sir Keir described failings in the probation service as a result of "a botched-then-reversed privatisation, after a decade of underinvestment" by the government.
Mr Sunak said "this was a truly terrible crime" and that the failings the chief inspector found "were serious and indeed, unacceptable".
He added: "In both of the cases that are in the public domain, these failures can be traced to failings in the initial risk assessment, and that's why immediate steps are being taken to address the serious issues raised."
Pressure mounts on Nadhim Zahawi to resign
Mr Zahawi has come under increased pressure after an investigation was launched into a multi-million pound HM Revenue & Customs settlement he made when chancellor to end a dispute.
A senior Tory joined calls for the party chair's resignation ahead of Wednesday's PMQs.
The prime minister's spokesperson has said Mr Sunak was not aware that Mr Zahawi had paid a fine to HMRC when he told the Commons last week that his chair "had addressed the matter in full".
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Chairman of the Committee on Standards in Public Life, Lord Evans, criticised the legal threats Mr Zahawi made as he tried to prevent stories about his tax affairs emerging.
Senior Conservative MP Caroline Nokes has called Mr Zahawi to "stand aside until this matter is all cleared up" but Mr Sunak has so far stood by him.
The prime minister ordered his ethics adviser to investigate whether Mr Zahawi broke ministerial rules over the estimated £4.8 million bill he settled with HMRC while chancellor.
Mr Sunak admitted there are "questions that need answering" as the inquiry was launched but argued it is "longstanding practice" for ministers to remain in their roles while under investigation.
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