Released US soldier Bergdahl in stable condition at hospital in Germany

This undated image provided by the U.S. Army shows Sgt. Bowe Bergdahl. (US Army)

Army Sgt. Bowe Bergdahl is in stable condition and receiving treatment for dietary conditions at Landstuhl Regional Medical Center in Germany, after arriving from Afghanistan, where he was held captive for nearly five years.

A statement from the Army hospital says Bergdahl arrived Sunday to begin his reintegration process before he returns to his family. Although privacy laws prevent the hospital from sharing details on his condition, the statement said his treatment includes “attention to dietary and nutrition needs after almost five years in captivity.”

How long he will remain in the hospital is unclear, but when he leaves Landstuhl, the military will transport him for medical care at Brooke Army Medical Center in San Antonio, Texas.

Bergdahl, 28, is under the care of a team of medical experts, which includes psychologists specializing in survival, evasion, resistance and escape treatment.

Pentagon spokesman Col. Steve Warren told reporters Monday there are three phases of reintegration. Phase 1 is an initial return into U.S. control. Phase 2 -- which Bergdahl is in now -- is conducted at a regional medical facility.

"It is a slow and deliberate process to make sure that the individual isn't overwhelmed by his reintegration back into society," Warren said.

Phase 3 is conducted in the U.S. and includes a homecoming, introduction into society and engagement with the media. Debriefing of Bergdahl will happen in all three phases. Investigators will determine if there is any information friendly forces can use for follow on operations. They are also likely to ask him about the circumstances of his disappearance.

Bergdahl has not yet spoken to his family, Warren said, but will as soon as he and his doctors decide he’s ready. It's too soon to determine if he will return to his unit or simply go home after the reintegration process.

Warren didn’t specifically comment on whether the Pentagon has ruled out prosecution for desertion or collaboration with the enemy charges for Bergdahl. Ultimately, U.S. Army leadership is responsible for determining if prosecution is necessary.

"There is plenty of time in the future to look into the circumstances surrounding his disappearance and to make decisions on the way forward," Warren said.

The Department of Defense has never confirmed that Bergdahl is a deserter, Warren said. The military has looked into the circumstances surrounding his disappearance, but “never publicly said anything primarily because we haven't had a chance to speak to Sgt. Bergdahl himself," Warren said.

All investigations up to this point are "preliminary," Warren said.

Fox News’ Justin Fishel and the Associated Press contributed to this report.