WASHINGTON >> Defense Secretary Lloyd Austin has canceled his trip to Brussels to meet with NATO ministers and work on Ukraine military aid as he remains hospitalized while dealing with further health issues following prostate cancer surgery, the Pentagon said Monday.

Austin, 70, was taken to Walter Reed National Military Medical Center on Sunday afternoon to address bladder issues and admitted to the intensive care unit. It was his second hospitalization this year in Walter Reed’s ICU following the surgery in December.

He underwent nonsurgical procedures Monday under general anesthesia to address the bladder issue, his doctors said in a statement released by the Pentagon.

“We anticipate a successful recovery and will closely monitor him overnight,” the statement said. “A prolonged hospital stay is not anticipated.”

Austin had been scheduled to travel to Brussels on Tuesday to attend a regular meeting of the Ukraine Defense Contact Group, a gathering of about 50 countries to coordinate military aid for Kyiv. That meeting will now be held virtually, the Pentagon press secretary, Maj. Gen. Pat Ryder, said.

Austin is planning to attend that virtual meeting, but if his condition prevents him from participating he will be represented by Celeste Wallander, the assistant secretary of defense for international security affairs.

White House national security spokesman John Kirby said Monday he did not know if President Joe Biden had spoken directly to Austin since he was hospitalized but that the president still had confidence in his ability to serve.

The Pentagon’s handling of Austin’s latest hospitalization is in marked contrast to how it handled his initial December diagnosis and treatment, which Austin and a few select members of his staff kept secret from almost everyone, including Biden. Austin has since apologized.

The decisions around not sharing that information with the president or public remain under review by the Pentagon’s inspector general. A separate internal review by the Defense Department has been completed, but not been made public yet.

It was not immediately clear if this bladder issue was a result of his prostate cancer treatment or a new health concern. In their statement Austin’s doctors said it is not expected to change his anticipated full recovery, and that Austin’s “cancer prognosis remains excellent.”

Austin transferred his authorities to Deputy Defense Secretary Kathleen Hicks on Sunday.

Following the Ukraine meeting, he was to attend a regular meeting of NATO defense ministers, also in Brussels. The U.S. ambassador to NATO, Julie Smith, will represent Austin at that meeting on Thursday, Ryder said.

In January, Austin spent two weeks at Walter Reed after he was taken there by ambulance in extreme pain following complications from his December prostate cancer surgery.