BBC, JUNE 1 --- Afghan Taliban leader Mullah Mohammad Omar has issued a rare public statement hailing the exchange of five Guantanamo Bay detainees for a Taliban-held US soldier as a "big victory".

Sgt Bowe Bergdahl, 28, was handed to US forces in Afghanistan on Saturday.

The White House has defended the swap amid criticism from Republicans who said the deal was soft on terrorism.

Sgt Bergdahl's parents said their son's recovery would take a long time, in an emotional address on Sunday.

Earlier on Sunday, Mullah Omar, who has made no public appearances or speeches since fleeing Afghanistan in 2001 when US-led forces toppled the Taliban after the 9/11 attacks in the US, said: "I extend my heartfelt congratulations to the entire Afghan Muslim nation."

The Afghan government, which was not informed of the deal until after the exchange had taken place, has condemned it as a "breach of international law".

"We are strongly opposed to it," it said in a statement, adding: "We want Qatar and the US government to let the men go free."

The five senior Afghan detainees are thought to be the most senior Afghans held at the US detention facility in Cuba, having been captured during America's military campaign in 2001.