Liam Gallagher believes his brother Noel still holds a grudge from him "p***ing" on his older sibling's new stereo.
The two brothers and former Oasis bandmates - who have rarely spoken since the group split in 2009 - shared a bedroom when they were younger, and the 'Wall of Glass' hitmaker thinks the 50-year-old musician still hasn't forgiven him for a drunken incident.
Asked where their rivalry began, Liam said: "We shared a bedroom and he'd bought this new soundsystem.
"I'd been out drinking, I was 15, had too many sherries, and I'd come in, and had a spliff as well, the room is spinning, I'd got out of bed, couldn't find the light switch so thought, 'F**k it, I'm gonna have to go man'.
"So I whipped it out, p***ed all over his new soundsystem and he's gone 'What the f**k are you doing? That's my f***ing new f***ing stereo?' 'It's alright, it'll f***ing dry won't it'. And I think he still holds a grudge from that and that was a long time ago.
"[The stereo] was the holy grail but when you gotta go, you gotta go, I ain't p***ing in my Paddington Bear pyjamas for no one."
The 44-year-old singer offered an apology of sorts to his brother, but it's not surprising Noel didn't accept.
Asked by US DJ Howard Stern if he'd apologised over the years, he said: "I said listen mate, it was either the soundsystem or your f***ing head, and I know he sleeps with his mouth open, so you take it or leave it my son."
Despite the tensions between them, the former Beady Eye singer still "loves" his brother but thinks he is "lost in celebrity world" and branded him a "stalker potato".
He said: "I love our kid, he's cool, just a bit lost in celebrity world. every time i see him he's got his arm round a crazy celebrity, it's like he's stalking them."
And asked about his infamous habits of sharing photos of Noel on Twitter and captioning them 'Potato', he explained: "Potato, you know what a potato is?
"Every time I see a couple of pictures of him and I just see a potato.
"Maybe it's just the way my brain is wired - pouting potato, angry potato, stalker potato. When he's got his arm round Bono, stalker potato."
The 'Wonderwall' singer still holds out hope that Oasis will reunite one day, but knows he and Noel need to repair their relationship first.
He said: "Without a doubt, that's my band. We've got to become brothers first before we can talk about the music, once we start liking each other, inevitable the next step is to take the band around the block for a spin.
"I love Oasis, it's the best thing ever."