Rishi Sunak faced a barrage of questions over Nadhim Zahawi’s tax dispute from Labour’s Sir Keir Starmer during Prime Minister’s Questions.
The Labour leader told the Prime Minister his failure to sack Mr Zahawi shows “how hopelessly weak he is” and accused the PM of overseeing chaos and being “overwhelmed at every turn”.
Mr Sunak has suggested it would have been "politically expedient" to sack the Conservative party chair but insisted that "due process" means the investigation by his ethics advisor into his tax affairs should be allowed to reach its conclusion.
The Prime Minister acknowledged that he had not been given the full picture about the Tory chairman's financial matters when he told MPs last week that Mr Zahawi had given a "full" account over the estimated £4.8 million bill he settled with HMRC.
But he insisted that when he entered No 10 and gave Mr Zahawi, who was not in the Commons for PMQs, the job of Minister Without Portfolio "no issues were raised with me".
David Gauke, the former Justice Secretary, earlier became the latest senior Conservative figure to call for Mr Zahawi to resign.
He told BBC Radio 4’s Today Programme that if he was the Prime Minister he would be “very tempted” to encourage him to stand down.
On Tuesday night, the former Attorney general Dominic Grieve told Newsnight: “If I were Prime Minister I would call Nadhim Zahawi in and I would say to him please explain exactly what’s happened. Because it doesn’t need an investigation. You’ve got to tell me what it is.
“And unless Nadhim Zahawi can make out the case that in this matter there’s been some unfortunate mistake which leaves him entirely blameless, it seems to me that following proper practice he ought to be resigning.”
But a Tory source said of Mr Zahawi this morning: “He is not resigning.