A "final Beatles record", created with the help of artificial intelligence, will be released later this year, Paul McCartney told the BBC in an interview broadcast on Tuesday.
"It was a demo that John (Lennon) had, and that we worked on, and we just finished it up," said McCartney, who turns 81 next week.
The Beatles -- Lennon, McCartney, George Harrison and Ringo Starr -- split in 1970, with each going on to have solo careers, but they never reunited.
Lennon was shot dead in New York in 1980 aged 40 while Harrison died of lung cancer in 2001, aged 58.
McCartney did not name the song that has been recorded but according to the BBC it is likely to be a 1978 Lennon composition called "Now And Then".
The track -- one of several on a cassette that Lennon had recorded for McCartney a year before his death -- was given to him by Lennon's widow Yoko Ono in 1994.
Two of the songs, "Free As A Bird" and "Real Love", were cleaned up by the producer Jeff Lynne, and released in 1995 and 1996.
An attempt was made to do the same with "Now And Then" but the project was abandoned because of background noise on the demo.
McCartney, who has previously talked about wanting to finish the song, said AI had given him a new chance to do so.
'Now and Then'
Working with Peter Jackson, the film director behind the 2021 documentary series "The Beatles: Get Back", AI was used to separate Lennon's voice and a piano.
"They tell the machine, 'That's the voice. This is a guitar. Lose the guitar'," he explained.
"So when we came to make what will be the last Beatles' record, it was a demo that John had (and) we were able to take John's voice and get it pure through this AI.
"Then we can mix the record, as you would normally do. So it gives you some sort of leeway."
McCartney performed a two-hour set at last year's Glastonbury festival in England, playing Beatles' classics to the 100,000-strong crowd.
The set included a virtual duet with Lennon of the song "I've Got a Feeling", from the Beatles' last album "Let It Be".
Last month, Sting warned that "defending our human capital against AI" would be a major battle for musicians in the coming years.
The use of AI in music is the subject of debate in the industry, with some denouncing copyright abuses and others praising its prowess.
McCartney said the use of the technology was "kind of scary but exciting because it's the future", adding: "We'll just have to see where that leads."
