Prince may have been dead for up to six hours before his body was discovered last month.

It was previously revealed that Prince died the day before he was due to meet with Dr. Howard Kornfeld, a national authority on opioid addiction treatment, about his addiction to painkillers.

Phaedra Ellis-Lamkins, who helped Prince recover the rights to his songs from Warner Bros., is believed to have contacted the doctor on his behalf, 12 hours before Prince died.

However, she would not comment except to say: "I cared deeply about him, and I am not ready to speak publicly. I also know how much he valued his privacy and want to respect his wishes."

Attorney William Mauzy, speaking on behalf of the Kornfeld family, has previously explained that while Howard could not travel from California immediately, he sent his son Andrew to go ahead and speak to Prince about his problem before he flew out the following day.

Mr Mauzy said: "The plan was to quickly evaluate his health and devise a treatment plan. The doctor was planning on a lifesaving mission."

However, when Andrew arrived at Prince's Paisley Park estate on April 21, Prince was nowhere to be found and he and two of the star's employees eventually found him unresponsive in an elevator.

According to Mr Mauzy, Andrew said the employees screamed when they found Prince and "were in too much shock" to call 911".

These claims came amid reports Prince had been addicted to painkiller Percocet for years because of problems with his hips and that he had to be given a "save shot" almost a week before his passing after he overdosed on the highly-addictive drug, which contains acetaminophen and oxycodone

Prince - who had used a cane to help him get around for many years - had long needed a double hip replacement but reportedly turned it down on numerous occasions but he was worried it would require a blood transfusion, which would have conflicted with his beliefs as a Jehovah's Witness.

The singer was rushed to hospital in Moline, Illinois on April 15 for the shot, which is administered to counteract the effects of opiates, after being taken ill on his private jet on the way back from a gig in Atlanta.