The former Oasis frontman lashed out at Robbie during a radio interview over his huge gigs at Manchester City's 60,000 capacity Etihad stadium, while his own band, Beady Eye played the city's rather more modest 1,500 capacity Ritz.
Speaking on 5 Live, he ranted: “We should be playing the Etihad three nights, not some f***ing fat f***ing idiot.
“It could be any f***ing clown. I think it’s a shame that he’s doing three nights and a band like us are doing one night in the Ritz.
“Poor, mate. It’s not about him, it’s people in general. But it is about f***ing him, just in case you think I’m scared or something.
“It’s a small gig. Beady Eye ain’t a big band.
“Everyone thinks we’re going to announce big f***ing stadiums. That [The Ritz] is the level we’re at and we’ll stay at that until you pull your f***ing finger out and buy the f***ing records.”
Robbie and Liam became mates in 1995 after he walked out on Take That and they spent a lost weekend together at Glastonbury.
Things soon turned sour after Liam's brother, Noel called him 'that fat dancer from Take That', but Robbie hit back by sending a wreath to Oasis when he beat their Knebworth live show record by selling out a third night.
And as Robbie collected a Brit Award in 2000, he challenged Liam to fight, pledging £100,000 to whoever won.
Robbie, over to you...