Richard Sharp’s selection as BBC chair is the subject of two separate investigations, amid allegations he helped Boris Johnson secure a loan of up to £800,000 weeks before he was recommended for the job by the then prime minister. The appointment of the prominent Conservative donor to lead the broadcaster is now being probed both by William Shawcross, the commissioner for public appointments, and by the BBC itself. Shawcross, who is responsible for ensuring that the process for recruiting roles at public bodies is not abused, said he had launched an investigation and requested the “relevant papers” from the Department for Digital, Culture, Media and Sport (DCMS). “The role of the commissioner is to oversee the public appointments process and ensure appointments are made fairly, openly and on merit,” Shawcross said in a letter to the shadow culture secretary, Lucy Powell. “I intend to review this competition to assure myself and the public that the process was run in compliance with the government’s governance code for public appointments, using my powers under the order in council 2019 and the governance code.” Sharp, who in the past has donated hundreds of thousands of pounds to the Conservative party, is coming under increased pressure over the affair. At the time of the recruitment process, Sharp introduced his friend Sam Blyth, a multimillionaire Canadian businessman and distant cousin of Johnson who had proposed to act as the then PM’s guarantor for a credit facility, to Simon Case, the cabinet secretary and head of the civil service. “What I did do was to seek an introduction of Sam Blyth to the relevant official in government,” said Sharp, who said he had one meeting with Case to facilitate the introduction. “We both agreed that to avoid any conflict that I should have nothing further to do with the matter. Since that meeting I have had no involvement whatsoever with any process.” The Cabinet Office has said the appointment process was “rigorous”, conducted according to the public appointments code, and that “all the correct recruitment processes were followed”. Sarah Healey, the permanent secretary at the Department for Digital, Culture, Media and Sport, who oversaw the process of shortlisting Sharp for the job, defended the process on Monday, pointing out that it had been given a clean bill of health by Shawcross’s predecessor Sir Peter Riddell. “The previous commissioner of public appointments did in fact do a detailed monitoring of this particular campaign and wrote to the DCMS select committee to set out his conclusions,” she said. “[That] included the fact that he was comfortable with the way that the competition had been running and praised the DCMS officials for the way that they had conducted it.” Riddell wrote to the DCMS committee last year, saying: “I am confident the panel used the published criteria for the role to assess each candidate fairly.” But he told the Guardian on Monday saying he welcomed a new review of the process, given the revelations about Johnson’s loan. “It is clear that there is additional information which wasn’t apparent to anyone involved two years ago, and it is quite right to have a review of the process,” he said, adding: “My inclination is that being transparent serves everyone’s best interests.” Separately he told Times Radio he thought Simon Case, the cabinet secretary, should have told Healey what he knew about the loan. “I think probably he should have made it aware to his colleague who’s chairing the panel,” he said. Meanwhile Sharp himself has asked the BBC nominations committee, which includes the director general, Tim Davie, and the corporation’s senior independent director, Nicholas Serota, to investigate whether there has been any conflict of interest since he joined as chair in 2021. The board has no powers to block or oust a BBC chair. Sharp said in an internal email to BBC staff on Monday: “I was not involved in making a loan, or arranging a guarantee, and I did not arrange any financing. We have many challenges at the BBC, and I know that distractions such as this are not welcomed. “Our work at the BBC is rooted in trust. Although the appointment of the BBC chair is solely a matter for the government, I want to ensure that all appropriate guidelines have been followed within the BBC since I have joined.” Johnson on Monday defended his role in appointing Sharp, saying: “Let me just tell you – Richard Sharp is a good and a wise man. But he knows absolutely nothing about my personal finances, I can tell you that for 100% ding-dang sure.” Downing Street meanwhile denied Sharp’s appointment was an example of “cronyism”. The prime minister’s spokesperson said: “There are processes in place to ensure that these appointments are done properly. That was followed in this instance.”