King Edward VII's Hospital in London, where the nurse who was duped into helping reveal details about the Duchess of Cambridge's health worked, has condemned the prank phone call as "truly appalling".
In a letter to the Australian radio station 2day FM's parent company, Lord Glenarthur, chairman of King Edward VII's Hospital, said he wanted to "protest" against the "extremely foolish" gag.
His comments follow the apparent suicide of nurse Jacintha Saldanha, 46, on Friday morning.
Lord Glenarthur said her death was "tragic beyond words".
The letter to Southern Cross Austereo said the immediate consequence of the station's "premeditated and ill-considered actions" led to the "humiliation" of Ms Saldanha and another nurse. "I appreciate that you cannot undo the damage which has been done but I would urge you to take steps to ensure that such an incident could never be repeated," it added.
A spokesman for the private London hospital said the letter was sent earlier on Saturday.
Ms Saldanha's devastated family were being comforted by relatives and friends at their terrace home at Greystoke Avenue, Southmead, Bristol.
A friend at the address said Ms Saldanha's partner Benedict Barboza, 49, and their teenage son and daughter, aged 14 and 16, were "very, very shocked and unhappy at the tragedy".
The devoted nurse and mother-of-two was pronounced dead at staff accommodation close to the hospital where the pregnant Duchess had been treated for a severe form of morning sickness.
News of her death led to a huge backlash against the two presenters, Mel Greig and Michael Christian, who broadcast the prank on their show on 2day FM. They have now been taken off the air while the Sydney-based station has been inundated with complaints