A senior Tory MP has called for the party chairman at the centre of a tax scandal to “temporarily recuse himself” from his role while an investigation into his conduct is carried out.

Nadhim Zahawi, chairman of the Conservative party and minister without portfolio, is facing an ethics probe into his tax affairs during his brief time as chancellor.

Opponents including Nicola Sturgeon and Sir Keir Starmer have called for Mr Zahawi to resign, labelled his position “untenable”.

Now Tory MP Caroline Nokes, chairwoman of the Commons Women and Equalities Committee, told BBC Breakfast Mr Zahawi should “stand aside until this matter is all cleared up”.

Read more: Investigation ordered into Nadhim Zahawi's tax dealings as chancellor

But current Tory ministers have rallied around Mr Zahawi, backing the Prime Minister’s call for him to remain in post while the probe is carried out.

Announcing the ethics probe into Mr Zahawi on Monday, Prime Minister Rishi Sunak said it is “longstanding practice” for ministers being investigated to remain in post.

Home Office minister Chris Philp said Mr Zahawi should be treated as “innocent until proven guilty” and it is “reasonable” for him to continue as party chairman.

Mr Zahawi is subject to an inquiry by the new independent adviser on ministers’ interests, Sir Laurie Magnus, into declarations about his tax affairs.

Read more: Nicola Sturgeon agrees to publish seven years of tax returns

He resolved a multimillion-pound tax dispute with HMRC by paying a penalty — reportedly around 30% of a £5 million settlement — while serving as chancellor under former prime minister Boris Johnson.

After Mr Sunak entered Downing Street in October, he appointed Mr Zahawi Conservative Party chairman and minister without portfolio, allowing him to attend Cabinet.

Policing minister Mr Philp said it is his understanding that Mr Sunak was told there were “no outstanding issues” in relation to Mr Zahawi’s tax affairs when appointing him to the roles in the autumn.

Mr Philp, asked on BBC Breakfast about Ms Nokes’s call for Mr Zahawi to step aside during the investigation, said: “I don’t take that view.”

He added: “We do have a principle, don’t we, in this country… innocent until proven guilty. That applies to a whole range of different circumstances.

“The investigation has been launched by the Prime Minister; that is the right thing to do.

“It will get to the bottom of this and then the Prime Minister will make his decision.

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“But I don’t think it is fair to jump to any conclusions before the investigation has concluded.”

Sir Laurie is expected to focus on Mr Zahawi’s ministerial declarations as part of his first probe since being appointed.

But the investigation could extend to his prior tax arrangement and whether he lied to the media.

Mr Philp said it will be for the ethics tsar to find out “the facts” behind what amounts to “carelessness” on Mr Zahawi’s part when it came to reporting his financial affairs to HMRC.

He told BBC Radio 4’s Today programme: “I don’t know what form that carelessness took and nor probably does anybody else apart from HMRC and Mr Zahawi, so let’s find out the facts.”

Labour said Mr Zahawi’s admitted carelessness should see him removed from Government.

Shadow foreign secretary David Lammy told Sky News: “When you’ve been chancellor of the exchequer and you said you’ve been careless despite the fact that offshore trusts have been set up in Gibraltar, I’m sorry, you really ought to resign or be sacked.”

Mr Zahawi, in a statement on Monday, said he is “confident” he has “acted properly throughout”.