AFP news agency reported on January 7 that US Defense Secretary Lloyd Austin took responsibility for not disclosing his recent hospitalization, after it emerged that even President Joe Biden and top White House officials were unaware.

The Pentagon waited until the evening of January 5 (local time) to announce that Secretary Austin (71 years old) had been hospitalized four days earlier "due to complications following a recent elective medical procedure". This is not in accordance with standard protocol.

NBC News reported that Mr. Austin had been in the intensive care unit for four days and was still in the hospital on January 6.

"I recognize that I could have done a better job of ensuring the public was properly informed. I am committed to doing better. But it is important to say: this was my medical procedure and I take full responsibility for my decision to disclose information," the US Secretary of Defense said in a statement.

He added that he would "return to the Pentagon soon" and thanked the doctors and staff at Walter Reed National Military Medical Center for their care.

The official's hospitalization comes amid heightened tensions in the Middle East over the Hamas-Israel conflict, attacks on shipping lanes by Iran-backed forces in Yemen, and attacks on US troops by forces in Iraq and Syria with rockets and drones.

Politico reported that Mr. Austin had been in the hospital for three days before Pentagon officials informed National Security Adviser Jake Sullivan and other top officials at the White House.

Mr. Sullivan then informed President Biden. In addition, it is reported that Congress only learned of Mr. Austin’s hospitalization 15 minutes before the public announcement on the evening of January 5.

US Congressman Tom Cotton, a Republican member of the Senate Armed Services Committee, demanded an explanation.

"The secretary of defense is a critical link in the chain of command between the president and the military, including nuclear command, when the most important decisions must be made within minutes. If this report is true, this shocking incident must have consequences," Mr. Cotton said.

The Pentagon Press Association expressed concern about the incident. "The public has a right to know when members of the U.S. government are hospitalized, sedated, or when duties are transferred for any medical procedure," the association wrote in a letter to the Pentagon press secretary.