BBC chairman Richard Sharp is facing calls for an investigation into his appointment, amid claims he helped Boris Johnson secure a loan – weeks before the then-prime minister recommended him for the role.

The former banker, who is in his 60s, worked for more than 30 years in the financial sector, including a 23-year stint at investment giant Goldman Sachs, where he was reportedly mentored by Prime Minister Rishi Sunak.

Before this, he worked in both commercial and investment banking for JP Morgan.

Mr Sharp, who read philosophy, politics and economics at Oxford University, is also a former chairman and an emeritus trustee of the Royal Academy.

He reportedly acted as an informal adviser to Mr Sunak at the beginning of the pandemic and played a key role in the creation of the Government’s £1.57 billion culture recovery fund.

He was also a member of the Bank of England’s Financial Policy Committee from 2013 until 2019, and sits on the board of the Centre for Policy Studies, the think tank founded by former prime minister Margaret Thatcher in the 1970s.

Mr Sharp’s appointment as chairman of the BBC, during one of the most turbulent periods in its history in February 2021, was widely regarded as political.

At the time, the corporation faced scrutiny over equal pay, diversity, free TV licences for the over-75s and competition from streaming services like Netflix.

Mr Sharp, who is a multimillionaire and has appeared on the Sunday Times Rich List, is a long-term donor to the Conservative Party and sat on Boris Johnson’s board of economic advisers when he was London mayor.

During his tenure at the BBC, he has defended the broadcaster on numerous occasions and used his platform to highlight the importance of journalism in speaking “truth to power” while lamenting the threat of disinformation faced by the industry.

In 2021, he denied the controversy over the hiring of Jess Brammar as head of news channels had “tainted” her appointment, after her impartiality was questioned following the emergence of old tweets in which she was critical of Brexit.

Last year he criticised the Government’s two-year freeze of the licence fee, describing it as “disappointing” and saying it will lead to “tougher choices” that will affect viewers.

But later in the year he said the board “welcomes an informed debate” about the future funding of the broadcaster and “nothing should be off the table”.

He also said former BBC presenter Emily Maitlis was “completely wrong” to suggest that “due process wasn’t followed” after she criticised the way the corporation handled her Newsnight speech about Dominic Cummings.

In an apparent reference to former prime minister Theresa May’s former communications director Sir Robbie Gibb, Ms Maitlis said there was an “active agent of the Conservative party” on the BBC board and that the corporation “sought to pacify” Number 10 after her monologue about the then-chief adviser’s trip to Durham during lockdown.

The chairman told the Digital, Culture, Media and Sport Committee (DCMS) that Ms Maitlis’s apparent description of Sir Robbie was “completely wrong” and he was “disappointed” she made that point.

Mr Sharp told the Sunday Times, which reported his alleged involvement in helping arrange Mr Johnson’s loan, that he had “simply connected” people and there was no conflict of interest.

Mr Johnson’s spokesman said the newspaper’s report was “rubbish” and that his financial arrangements “have been properly declared”.