WASHINGTON (AP) — Defense Secretary Lloyd Austin returned to work at the Pentagon on Monday after nearly a month’s absence because of prostate cancer and met with NATO Secretary General Jens Stoltenberg.

Austin expressed his gratitude for returning to the Pentagon during this crucial moment. He stated at the beginning of the meeting, “I am pleased to be back and am doing well in my recovery. I am grateful for the kind messages I have received so far.”

Following the session, Austin attended a meeting with the national security team at the White House Situation Room to discuss the drone strike at a base in Jordan that resulted in the deaths of three American soldiers and injuries to numerous others.

On December 21st, he was last seen in the Pentagon. He had received a diagnosis of prostate cancer earlier in the month and on December 22nd, he underwent a surgical procedure for the cancer at a hospital. The following week, he worked remotely from home.

On January 1, an ambulance transported him to Walter Reed National Military Medical Center due to severe pain. He was then admitted to the intensive care unit and remained there for two weeks. However, he did not disclose his cancer diagnosis, surgery, or return to the hospital until several days later, neither to the White House nor his deputy. It wasn’t until over a week had passed that he informed President Joe Biden and other important officials about his condition.

Austin’s failure to disclose information has led to modifications in government standards and has initiated an internal investigation by the Pentagon and an inspection by the department’s inspector general to evaluate their notification protocols. Both evaluations are still in progress.

Austin has been telecommuting since his release from the hospital on January 15th. He recently made his initial public appearance during a virtual gathering of the Ukraine contact defense group. He delivered an introductory speech for the meeting through a live video feed that was broadcast online.

On Friday, physicians at Walter Reed reported that Austin’s prognosis for prostate cancer is very positive and he will not require any additional treatments. He visited doctors for a routine examination on Friday.

Austin received backlash for not disclosing his prostate cancer diagnosis, surgery, and hospitalization due to complications.

In the beginning of December, he received a diagnosis and underwent a “minimally invasive” surgery, known as a prostatectomy, on December 22 to address the cancer. He was unconscious during the procedure and delegated some responsibilities to his deputy defense secretary, Kathleen Hicks. He was released from the hospital the following day and remained actively involved in his duties.