The chairman of the BBC quit Friday after a report found he failed to disclose a potential conflict of interest over his role in arranging a 2021 loan for Boris Johnson, who was the U.K.’s prime minister at the time.

The publicly funded national broadcaster has been under political pressure after it was revealed that Richard Sharp helped arrange the line of credit weeks before he was appointed to the BBC post on the government’s recommendation.

The 800,000 pound ($1 million) line of credit came from wealthy Canadian businessman Sam Blyth, who was introduced to Johnson by Sharp, a Conservative Party donor. Johnson was the party’s leader as well as British prime minister.

Sharp said he was quitting to “prioritize the interests of the BBC” after making an “inadvertent” breach of the rules.

“I feel that this matter may well be a distraction from the corporation’s good work were I to remain in post until the end of my term,” he said.

Sharp said he would remain in his BBC role until the end of June while the search for a successor takes place.

A report on the incident by senior lawyer Adam Heppinstall published Friday found Sharp “failed to disclose potential perceived conflicts of interest.”

The investigation is the latest uncomfortable episode for the 100-year-old BBC, which is funded by a license fee paid by all households with a television and has a duty to be impartial in its news coverage.

The public broadcaster is frequently a political football, with some members of the Conservative government seeing a leftist slant in its news output and some liberals accusing it of having a conservative bias.

The BBC was engulfed in a storm over free speech and political bias in March when its leading sports presenter, former England soccer player Gary Lineker, criticized the government’s immigration policy on social media.

Lineker was suspended – and then restored after other sports presenters, analysts and Premier League players boycotted the BBC airwaves in solidarity.