Dr. George Tidmarsh, the Food and Drug Administration’s top drug regulator, was placed on administrative leave and is considering resigning, citing a “toxic” environment at the FDA.

Tidmarsh, who leads the FDA’s Center for Drug Evaluation and Research, was placed on leave Friday “after the Office of the General Counsel and the Office of the Inspector General were notified of serious concerns about his personal conduct,” Emily Hilliard, an HHS spokeswoman, told ABC News in a statement.

STAT News, a health, science and medicine-oriented publication, reported Sunday that Tidmarsh was accused of using his regulatory authority to financially harm a former business associate. 

Tidmarsh denied the allegations in an interview with ABC News on Sunday night.

He claimed the move was in retaliation for his speaking out against Vinay Prasad, the FDA’s chief medical and scientific officer.

Tidmarsh said he had criticized a new regulatory process at the FDA designed to speed up the review process for certain drugs. Tidmarsh raised concerns about the legality of the arrangement, which uses a tumor board-style review process to fast-track approvals for “companies aligned with critical U.S. national health priorities,” according to an FDA description of the program. 

He told ABC News the arrangement, as designed, would be “different than the entire history of decades of the FDA.”

“It circumvents rigorous scientific debate and puts Vinay Prasad in charge of every drug approval,” he said.

Hilliard, the HHS spokeswoman, did not respond to a question about Tidmarsh’s claims of retaliation.

“Secretary Kennedy expects the highest ethical standards from all individuals serving under his leadership and remains committed to full transparency,” she wrote.

Though Hilliard said Tidmarsh had resigned on Sunday, Tidmarsh told ABC News he was still weighing whether to do so.

“I would resign from a place as toxic as the current environment,” he alleged of the FDA. “It’s toxic, it’s bad, it’s bad for the American people. Anybody with a right mind would get out of a situation like that.”