British singer George Michael’s cause of death remains unknown after an initial autopsy has been declared “inconclusive”.

The 53-year-old was found in bed at his home in Oxfordshire, United Kingdom, by his Australian-born partner Fadi Fawaz on Christmas Day.

UK police released a statement that said, “a post mortem examination was carried out yesterday as part of the investigation into the death of George Michael.”

“The cause of death is inconclusive and further tests will now be carried out,” they continued.

“The results of these tests are unlikely to be known for several weeks.”

George Michael

The nature of Michael’s death is said to be “unexplained but not suspicious”.

Following the news which broke on Boxing Day, Michael’s manager, Michael Lippman, released a statement outlining that the British singer had died of heart failure.

“I’m devastated,” he told

Billboard

. “(There was) no foul play whatsoever.”

"It doesn't get any much better than this. The most beautiful view and the most beautiful man," Fawaz wrote alongside this 2012 image. Source: Twitter.

Fawaz, 46, posted to Twitter on Boxing Day "It's a xmas i [sic] will never forget finding your partner dead peacefully in bed first thing in the morning...I will never stop missing you xx."

ITs a xmas i will never forget finding your partner dead peacefully in bed first thing in the morning.. I will never stop missing you xx

— Fadi Fawaz (@fadifawaz) December 26, 2016

Sir Elton John posted a moving tribute to Instagram following the news of his death, with the message. “I am in deep shock. I have lost a beloved friend – the kindest, most generous soul and a brilliant artist.”

John is reported to be performing at the late pop star's funeral.