US Secretary of Defence Chuck Hagel said it was unfair to jump to conclusions about released captive Sgt Bowe Bergdahl until the circumstances around his capture by the Taliban had been reviewed.
Mr Hagel said:" "We don't do that in the United States. We rely on facts.
"It's not my place as a former sergeant in the Army to decide who's worthy of being a sergeant and who isn't."
Sgt Bergdahl had been held in Afghanistan for five years but was released on Saturday amid speculation that he might face desertion charges.
Mr Hagel said the army would review all the circumstances surrounding how he left his unit and was captured by the Taliban.
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