One of the Australian DJs who made a prank phone call to the hospital where the Duchess of Cambridge was being treated for acute morning sickness is back on air.

Michael Christian was suspended in December after he and Mel Greig phoned King Edward VII's Hospital in London and pretended to be the Queen and Prince Charles inquiring about the Duchess of Cambridge.

Jacintha Saldanha, the nurse who transferred the hoax phone call, killed herself three days after the call.

Christian has returned to broadcasting, hosting a morning slot on the Melbourne music station Fox FM, part of the Southern Cross Austereo network which owns 2 Day FM, the station where the prank phone call was made from.

Christian did not mention the controversy iver the prank during his first broadcast and he will not be making or taking any phone calls in his new show.

Southern Cross Austereo chief executive Ryhs Holleran said: "We are happy to have Michael back on air. We have always supported our talent returning to work when appropriate and today marks that occasion for MC."

Christian's former co-host has yet to return but Holleran added: "We look forward to welcoming Mel Greig back when the time is right."

The Crown Prosecution Service has confirmed that the two DJs would not face criminal charges following the death of Saldanha.

In a statement, the CPS said it had taken into account the fact that, despite the tragic outcome, the telephone call was "intended as a harmless prank".

Following the death of mother-of-two Saldanha, Christian and Greig made a tearful apology in which they said they were "heartbroken" at the incident.