English boxing promoter Frank Warren is reportedly preparing to sue Zuffa Boxing and TKO Holdings Group for $1 billion. Warren’s British-based Queensberry Promotions has sent letters to Saudi Arabia’s Sela and TKO Group Holdings stating its intention  to sue both for breach of contract over the formation of Zuffa Boxing. According to a report by  The Telegraph , Queensberry is seeking up to $1 billion for income the promotion alleges it would have earned had its contractual agreements been honored.