Health and Human Services Secretary Tom Price, who faces mounting criticism over his use of charter flights for routine travel around the country, said Thursday he would personally reimburse the federal government for the travel.

“I regret the concerns this has raised regarding the use of taxpayer dollars,” Price said in a statement announcing the decision.

“All of my political career I’ve fought for the taxpayers,” he added. “It is clear to me that in this case, I was not sensitive enough to my concern for the taxpayer.”

Price’s unusual use of charter flights was first reported by Politico, which has documented more than two dozen charter flights taken by Price, costing taxpayers more than $400,000.

The flights included visits to a resort where Price owns land and to a lunch with his son.

The travel is now the subject of an investigation by the inspector general’s office at the Health and Human Services Department.

The House Oversight Committee has also asked the White House and various agencies to turn over information about any private flights.

Price, an orthopedic surgeon and former Republican congressman from Georgia, faced ethics questions after his nomination over reports that he traded extensively in the stock of health care companies even as he pursued legislation that would have affected some of the same companies.

President Donald Trump said Wednesday that he was “not happy” with Price’s travel, stoking speculation that Price might be forced to resign. Price appeared to allude to that possibility in his statement Thursday.

“I have spent 40 years both as a doctor and in public service putting people first,” he said. “It has been my personal honor to serve the American people, and I look forward to continuing that service.”