Deputy press secretary Sabrina Singh said Austin was in "good condition" and was expecting to be discharged "later today" -- promising a further update when he resumes his full duties and functions.

The 70-year-old was admitted to a critical care ward on Sunday and transferred duties to his deputy Kathleen Hicks, who remains in charge for the time being, Singh said.

Austin's latest health scare came weeks after it emerged he had kept recent hospital stays secret and had not promptly informed President Joe Biden of his cancer diagnosis, sparking widespread criticism.

He "underwent non-surgical procedures under general anesthesia," his doctors at the Walter Reed National Military Medical Center outside Washington said Monday in a statement.

Austin is a key figure in efforts by the United States to shore up Western support for Ukraine's fight against Russia's invasion, as Republican lawmakers in Washington refuse to fund new military aid to Kyiv.

He had been scheduled to attend a meeting in Brussels of the Ukraine Defense Contact Group of nations coordinating military assistance, but the Pentagon canceled those plans and announced the meeting would instead be virtual.

Singh said Austin was still planning to give opening remarks at the virtual version of the gathering.

She echoed previous Pentagon statements that the bladder issue was unrelated to his cancer treatment.

Austin's health issues come with the United States facing an escalating crisis in the Middle East sparked by the October 7 attacks on Israel by Hamas militants.

He vanished from public view as he underwent cancer treatment in December and again in January after he suffered complications.

Austin has gained a reputation as an apolitical official who eschews the spotlight, which he said played into his decision to keep his cancer diagnosis secret.

He publicly apologized for not revealing the hospitalizations, and the administration has launched investigations into how the chain of command operates when senior officials are incapacitated.

"Frankly, my first instinct was to keep it private. I don't think it's news that -- I'm a pretty private guy -- I never liked burdening others with my problems," he said.

National Security Council spokesman John Kirby was asked by reporters on Monday if Biden had any concerns over Austin's ability to continue in his job, and he replied: "Not at all."