As one of his final acts in office, US President Barack Obama has commuted the sentence of Chelsea Manning.

She's one of 209 prisoners whose sentences he's reduced while 64 people prisoners have been pardoned - and it's expected she'll be out in May.

Manning, who was born a male but now identifies as female, was convicted of espionage in 2013.

The former army intelligence analyst was found guilty of providing more than 700,000 documents, diplomatic cables, videos and battlefield accounts to the Wikileaks in what is believed to be the largest breach of classified materials in US history.

Kim Buckley has this report: