Sir Ringo Starr was all set to open a hair salon because he didn't think The Beatles would "last a week".

The legendary Liverpool group's final song, 'Now And Then', was released last week, some 63 years after they first formed in 1960.

The 'Eleanor Rigby' hitmakers - also comprised of the late frontman John Lennon and drummer George Harrison - split in 1970 and surviving members Starr, 83, and Sir Paul McCartney, 81, have admitted they didn't anticipate lasting as long as they did.

In an interview with The Sunday Times, McCartney said: “When we started, we thought that, maybe, we’d have ten years."

Starr continued: “None of us thought it would last a week!

“Paul was going to write, I was going to open a hairdresser’s, George would get a garage. But it went on and then it ended. And at the right time, I think. But, you know, that didn’t stop us playing with each other.”

Little did they know they would become one of the biggest bands of all time and that their music would still resonate to this day.

Starr added: “How many streams did we do last year? One billion? Three billion? It blows me away… The beat’s still going on, you know?”

The 'Let it Be' hitmakers are on track to earn their 18th number one single with 'Now And Then'.

McCartney recently said he thinks John "would have loved" the new Beatles song.

The Artificial Intelligence-assisted track features a demo recorded by Lennon before he was killed in December 1980 at the age of just 40.

Recorded after The Beatles broke up, it features his voice and him playing the piano at his New York apartment, with AI technology used to isolate and improve his vocal.

In new documentary 'Now And Then - The Last Beatles Song', McCartney said: "We listened to the track. There’s John in his apartment in New York City, banging away at his piano, doing a little demo.

"Is it something we shouldn’t do? Every time I thought, like that, I thought ‘wait a minute.’

"Let’s say I had a chance to ask John. ‘Hey John, would you like us to finish this last song of yours?’ I’m telling you, I know the answer would have been ‘yeah.’ He would have loved that.”

John's son Sean Lennon agrees taht his father would have approved of the project.

He added: "My Dad would've loved that because he was never shy to experiment with recording technology. It's really beautiful."

Following Lennon's initial demo, the track was later worked on by McCartney, Starr and Harrison in 1994 when the trio finished 'Real Love' and 'Free As A Bird'.

However, Lennon's recordings made 'Now And then' impossible to complete at the time, but new technology - which was also used to enhance the audio in Peter Jackson’s docuseries 'The Beatles: Get Back' - means the two surviving members have finally finished the song.

McCartney recalled: "They said this is the sound of John's voice [imitates computer noise'.

"A few seconds later and there it was, John's voice, crystal clear. It was quite emotional."