The Bee Gees manager Robert Stigwood has died at the age of 81.

Robert Stigwood with Sarah Ferguson

Robert Stigwood with Sarah Ferguson

The Australian music mogul's passing was confirmed on Facebook by Spencer Gibb, the son of late Bee Gees star Robin Gibb, in a touching post.

At the time of writing a cause of death was not known.

In his social media post, Spencer wrote a moving tribute to Stigwood who he knew as "Stiggy" and who steered his father's group to worldwide fame and success.

He wrote on his Facebook page: "My godfather, and the long-time manager of my family, Robert Stigwood, has passed away. A creative genius with a very quick and dry wit, Robert was the driving force behind The Bee Gees career ... I would like to thank Robert for his kindness to me over the years as well as his mentorship to my family. "Stiggy", you will be missed."

Stigwood worked in advertising in his native Australia before moving to the UK at the age of 21 to enter the music and film industry.

He made his name representing English singer John Leyton, securing him a role on the TV show 'Harpers West One', and he went on to record a song 'Johnny Remember Me' which spent four weeks at number one in 1961.

After a period on bankruptcy, in 1966 he became a booking agent for The Who before signing them to his own Reaction Records label, where they recorded the hit single 'Substitute'.

He then managed Cream and Eric Clapton, before signing the Bee Gees in 1967 and going on to forge a working relationship with three brothers, Barry, Robin and Maurice which lasted a lifetime.

In 1968, he began working in musical theatre and his company The Robert Stigwood Organisation (RSO) oversaw the productions 'Hair'

'Oh! Calcutta!', 'Sweeney Todd' and eventually the last of the Tim Rice and Andrew Lloyd Webber musicals 'Evita'.

Lord Lloyd Webber has taken to his Twitter account to pay tribute to his late friend, writing: "Farewell beloved Robert, the great showman who taught me so much. With love, ALW. (sic)"

Elaine Paige - who starred the original run of 'Evita' - also took to Twitter to remember Stigwood, writing: "Upsetting news: passing of legend Robert Stigwood (who,amongst so much,produced theatre prods incl #Evita) ... RIP (sic)"

Stigwood also turned his attention to movies and acted as the producer on 'Grease' and 'Saturday Night Fever' - for which the Bee Gees provided the acclaimed soundtrack.

He was responsible for casting fellow Australian Olivia Newton John in the role of Sandy in 1978 hit movie 'Grease', which also starred John Travolta in the part of Danny Zuko.