The British siblings shot to fame in the 1990s when Liam was the singer in the group and Noel was the guitarist and principle songwriter.
They split in 2009 following a series of increasingly bitter bust-ups between the two, and now Liam has aired his suspicion that his brother had been secretly planning a solo career for years.
He tells Q magazine, "Noel wanted out, man, don't be f**king kidded. He always wanted to be a frontman. He loves being in the f**king spotlight, being in charge. All that c**p about, 'This has been thrust upon me, let's deal with it together.' F**k off, you've been planning it for years, you c**t."
Liam went on to form a new band, Beady Eye, while his brother now fronts Noel Gallagher's High Flying Birds.