Obama says the US has a basic principle of not leaving any service man or woman behind and said Bergdahl's health had been deteriorating. He says, quote, "we were deeply concerned about it."
Obama spoke during a joint news conference with British Prime Minister David Cameron in Brussels.
Bergdahl was released following a deal between the US and the Taliban that was brokered by Qatar. Five Taliban detainees held in Guantanamo were released as part of the exchange.