WASHINGTON (NewsNation) — Under fire for his hospital stay last month, Defense Secretary Lloyd Austin told Congress Thursday that the Department of Dense has made changes to improve the notification process if he must transfer decision-making authorities due to illness or lack of communication.

He said there were no gaps in control of the department or the nation’s security because “at all times, either I or the deputy secretary was in a position to conduct the duties of my office.”

The House Armed Services Committee hearing comes after several lawmakers have called for Austin’s resignation due to his failure to quickly notify administration officials about his hospitalization and stay in the intensive care unit following complications from prostate cancer surgery.

“It’s totally unacceptable that it took three days to inform the president of the United States that the secretary of defense was in the hospital and not in control of the Pentagon,” House Armed Services Committee Chair Rep. Mike Roger, R-Ala., said during opening statements.

He added: “Wars were raging in Ukraine and Israel, our ships were under fire in the Red Sea, and our bases were bracing for attack in Syria and Iraq. But the commander in chief did not know that his secretary of defense was out of action.”

Austin apologized for being secretive after his diagnosis and hospitalization became public, admitting in opening statements, “We did not handle this right. I did not handle this right.”

He added that there was a “breakdown in notifications” while he was hospitalized and that he takes “full responsibility” for the lapse. He said he never instructed any members of his staff to keep his hospitalization secret.

Austin told lawmakers that the DOD has made changes to improve the notification process if he must transfer decision-making authorities due to illness or lack of communication.

However, Rogers and others said someone needs to be held accountable.

The incident led to concerns about lapses in the command and control of the armed forces, including the country’s nuclear arsenal.

The Pentagon has said Austin’s staff notified Deputy Defense Secretary Kathleen Hicks when Austin went into intensive care in early January. But that only raised questions about why Austin didn’t do that himself and whether that suggested there was a gap in control.

Austin said at the committee hearing that “at no time during my treatment or recovery were there any gaps in authorities.” He offered a mea culpa that mirrored remarks early this month at a news briefing, saying he takes full responsibility for the communications failures and that he has apologized to Biden.

Acknowledging the breakdown in communications, he added, “I should have promptly informed the president, my team, Congress, and the American people about my cancer diagnosis and subsequent treatment. Again: We did not handle this right. And I did not handle it right.”

Austin, 70, underwent a medical procedure related to prostate cancer at Walter Reed National Military Medical Center on Dec. 22. He went home a day later and was admitted to intensive care Jan. 1 when he began experiencing severe pain.

Senior military officials and White House officials, including President Joe Biden, weren’t informed of his condition until several days later.

Earlier this month, Austin acknowledged communication mistakes and said he should’ve handled the incident better. He added his decision was more about privacy than secrecy.

The Pentagon released a review revealing there had been no deliberate attempt by Austin or his aides to keep the hospitalization secret. Additionally, the report noted policies for transferring Austin’s responsibilities during an emergency must be improved.

The review didn’t provide additional details on what was already known about the timeline of Austin’s hospitalization.

Rogers criticized the report for failing to provide answers for who knew what, when, and who failed to perform their basic duties.

“We were led to believe your 30-day internal review would shed light on the matter. But it includes no explanation of why the President and his staff were left in the dark. It makes no recommendations to improve communication with the White House. And unsurprisingly, it holds no one accountable,” Rogers said.

Thursday’s hearing was one of the most contentious and personal that Austin, a retired four-star general, has faced in his career. It was also the first time Austin has testified on Capitol Hill since last fall.

The Associated Press contributed to this report.