Keith Richards thinks Sir Mick Jagger should have a vasectomy.
The 74-year-old guitarist branded his Rolling Stones bandmate - who became a father for the eighth time in December 2016 when girlfriend Melanie Hamrick gave birth to their son Devereaux - a "randy old b*****d" and insisted the 74-year-old singer is too old to keep having children.
He told Wall Street Journal magazine: "Mick's a randy old b*****d.
"It's time for the snip - you can't be a father at that age. Those poor kids!"
The two rockers have publicly traded insults over the years, and though Keith admitted they "live off of this fire" between them, he also acknowledged the 'Satisfaction' singer is the best frontman he could work with.
He added: "Mick and I live off of this fire between us."
"If I'm talking about the Rolling Stones, there ain't a frontman like Jagger. Don't matter how many bones you want to pick out of him, he's amazing to work with."
But following the publication of the interview, the 'Brown Sugar' musician has issued a public apology to his bandmate, insisting he was "completely out of line" and admitted he had also said sorry in person.
He tweeted: "I deeply regret the comments I made about Mick in the WSJ which were completely out of line. I have of course apologised to him in person."
This isn't the first time Keith has hit out at Mick as he has also called him a "snob" and "control freak".
He said: "He's such a snob. He can come off that way even to me and the rest of the band. He comes on the plane and doesn't say, 'Hey mate'. He's preoccupied with something really boring. He's a control freak. He likes to know everything that's going on. He lost himself a bit in the details."
But their most famous fall out in recent years came after the guitarist dubbed his bandmate "that b***h Brenda" and claimed he had a "tiny todger" in his 2010 autobiography 'Life'.
He added in the tome: "I know he's got an enormous pair of balls - but it doesn't quite fill the gap."
Keith apologised to Mick after the frontman insisted it was a "prerequisite" before they embarked on a tour in 2013, but the 'Paint it Black'' rocker later hinted he may not have been entirely sincere.
He said: "We resolved it, in our own way, you know. I said I regret if I caused you any, you know, inconvenience or pain, or something. I'd say anything to get the band together, you know? I'd lie to my mother."