Prime Minister Rishi Sunak has asked his independent ethics adviser to look into the tax affairs of Conservative Party chairman Nadhim Zahawi.
Mr Sunak said there were “questions that need answering” over the case.
Mr Zahawi is facing calls to resign, after it emerged he paid a penalty to HMRC over unpaid tax while he was chancellor, as part of a multi-million pound dispute.
He has described the error as “careless and not deliberate”.
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