George Harrison with his wife, Olivia
The former Beatle has recorded a single with musician Jools Holland.
Harrison, 58, wrote the track entitled A Horse To Water with his son Dhani.
He recorded the song at home on 1 October, less than six months after undergoing radiotherapy for a brain tumour.
'Intrigued'
"It is not a ballad and it is not rock. I think George Harrison fans will be intrigued," said the spokesman.
Harrison was treated for a brain tumour this year and had previously been treated for lung cancer and throat cancer.
The star has rarely recorded new material over the past few years, although he did re-record his hit My Sweet Lord for the re-issued album All Things Must Pass.
Duets
The new track will appear on Holland's album Small World, Big Friends, to be released in the UK on 19 November.
The album includes Holland performing duets with some of the biggest names in music including Eric Clapton and Dire Straits' Mark Knopfler.
Harrison revealed a dark sense of humour on the new track. with a publishing credit to RIP Ltd 2001 on the track listing.
Holland - who presents the Later show on BBC Two - visited Harrison's villa in Switzerland, with singer Sam Brown, to record the track.
'Legendary'
He said he and Harrison became friends after working on a Channel 4 documentary together.
"Years later I interviewed George, Paul and Ringo for the Beatles Anthology documentary and George and I had regular cups of tea together," he said.
"George suggested we do a track and this finally happened this month. It was wonderful to work with one of the great, legendary artists in the world."
Harrison, the youngest Beatle, was angered by reports in July this year that he was preparing for death due to his illness.
He released a statement in July saying that reports he was close to death "were unsubstantiated, untrue, insensitive and uncalled for".
Two years ago he and his wife Olivia survived an attack by an intruder at their home in Henley-on-Thames, Oxfordshire in 1999, in which Harrison was stabbed.