The Gallagher brothers, who stormed British pop in the 1990s when they were together in rock band Oasis, have taken their increasingly bitter war of words to court.
Younger sibling Liam, former lead singer of the group who now fronts Beady Eye, issued a statement on Friday confirming he was suing songwriter and guitarist Noel for comments he made over why the band broke up in 2009.
Noel, 44, who made the remarks during a press conference in July at which he was launching his solo career, had no immediate comment to make on the lawsuit at London's High Court, his spokesman said.
Liam said in his statement: I have taken legal action against Noel Gallagher for statements he made during the Electric Cinema press conference on July 6 during which he claimed Oasis pulled out of the 2009 V Festival Chelmsford gig because I had a hangover.
That is a lie and I want Oasis fans, and others who were at V, to know the truth.
He went on to explain he was gutted to have had to pull out of the event, and that the real reason was laryngitis as diagnosed by a doctor and explained to Noel.
Noel also falsely stated that the demise of Oasis followed a massive row in which he claimed I demanded to advertise my clothing range Pretty Green in the Oasis tour program, he added.
The truth is there was no such discussion or row between us. There are many reasons why Oasis split. But it had nothing to do with my clothing range.
Noel had said little about the infamous break-up of one of Britain's most successful bands until the July briefing, when he gave his version of events in Paris two years ago.
Liam, 38, said the case was not about money but about extracting an apology from his brother.
I am used to being called all sort of things by Noel and I have in the past said things about him, but what Noel has alleged this time went way beyond rock-and-roll banter and questioned my professionalism.
Oasis, famous for swirling rock hits including Don't Look Back in Anger, Wonderwall and Champagne Supernova, has sold an estimated 70 million albums worldwide.