British singer David Bowie performs during the first concert of his UK tour in Manchester
British singer David Bowie performs during the first concert of his UK tour in Manchester, November 17, 2003. Pictures of the month November 2003. Reuters/Ian Hodgson

British musician and actor David Bowie died on Sunday at the age of 69 after a 18-month battle with cancer. His long-time friend, collaborator, musician and producer Brian Eno revealed the contents of the final email he received from the late rock icon.

"It was as funny as always, and as surreal, looping through word games and allusions and all the usual stuff we did. It ended with this sentence: 'thank you for our good times, Brian. they will never rot' and it was signed 'dawn,'” Eno said in a statement issued to BBC News.

One of the principal innovators of ambient music, Eno knew Bowie for over forty years and realises that the email was effectively Bowie’s farewell to him: "I realise now he was saying goodbye."

Over the years, Eno collaborated with Bowie on a number of albums, including the famous Berlin-Trilogy (1977-1979).

"David's death came as a complete surprise, as did nearly everything else about him. I feel a huge gap now,” Eno said.

Eno also said that it was only a year ago that the two were talking about their last album together: "About a year ago we started talking about Outside -- the last album we worked on together. We both liked that album a lot and felt that it had fallen through the cracks. We talked about revisiting it, taking it somewhere new. I was looking forward to that.”

Eno described how the two had kept in contact with each other through emails and likened the pair's friendship to that of comedy duo Peter Cook and Dudley Moore, known as Pete and Dud; how they used to sign off with humourous aliases.

"We knew each other for over 40 years, in a friendship that was always tinged by echoes of Pete and Dud. Over the last few years - with him living in New York and me in London -- our connection was by email. We signed off with invented names: some of his were mr showbiz, milton keynes, rhoda borrocks and the duke of ear.”

Another of Bowie's collaborators and producer of his twenty-fifth and final studio album "Blackstar," Tony Visconti, confirmed on Monday the legendary singer created the album as a “parting gift.”

In fact, the single Lazarus, part of the album “Blackstar,” released on the Bowie's 69th birthday just two days before his death, opens with the lyrics: “Look up here, I'm in Heaven!” The video features the musician in a hospital bed, and finishes with him retreating in to a dark closet.

Bowie first tasted fame in 1972, when he unveiled his androgynous alter ego, Ziggy Stardust, which made him a cult figure, an icon in the world of rock music. He continued with that glam-rock persona and produced albums for Lou Reed and Iggy Pop, before retiring the Stardust character in 1973.

In 1975, he co-wrote with John Lennon his first No. 1 hit in the U.S., "Fame."

Bowie’s acting career was also diverse, notably the cult classic film by Jim Henson, “Labyrinth,” where he played the role of Jareth the Goblin King. Two years later, he played Pontius Pilate in Martin Scorsese's 1988 film “The Last Temptation of Christ.”

He also portrayed famous innovator Nikola Tesla in Christopher Nolan’s “The Prestige" (2006). His last proper film role was in Austin Chick’s “August” (2008), where he re-united with Rip Torn, with whom he had worked in “The Man Who Fell to Earth” in 1976.