Paul McCartney says Keith Richards once told him that the Rolling Stones envied the fact that all the members of the Beatles were singers. He revealed details of the conversation in a new interview with the BBC's Radio Times.

"I talked to Keith Richards recently … well, a couple of years ago, and his take on it was: 'Man, you were lucky, you guys, you had four lead singers,' whereas the Rolling Stones only had one," divulges Macca.

"I could sing, John could sing, George could sing and Ringo did numbers that he could sing," adds McCartney. "So, it wasn’t just the front man and the back-up band. We were an entity. Mick [Jagger] used to call us the Four-Headed Monster. We would show up at places all dressed the same."

In the same interview, McCartney talks about how the band waited until they had a chart-topping hit before coming to the United States. "We saw a lot of British acts go to America, and come back not having had the great success we thought they would have," he explains. "It was very clear in my mind. We cannot go there until we have cracked it with a record."

He also talks about how the Beatles were very close to not existing at all. There had been a law in England that required young men to serve one or two years of military service. Luckily, the law was repealed the same year the band got together. "A couple of years earlier, we would have been in the Army, and it’s very doubtful that the Beatles would have formed," says Macca.

Watch Footage of the Beatles Recording 'Get Back' with the Rolling Stones Looking On

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