LONDON -(Dow Jones)- Oil and gas group BG GROUP PLC (BG.LN) said Tuesday that it has signed a definitive binding agreement with Brazil's Cosan S.A. Industria e Comercio for the sale of the BG's entire 60.1% holding in gas distributor Comgas for BRR3.4 billion in cash, or $1.7 billion at current exchange rates. MAIN FACTS: -Transaction will reduce debt on the BG Group balance sheet by some $1.1 billion. -The transaction, which is subject to regulatory approval, is likely to complete by the end of 2012. -Further, BG Group and Cosan have agreed, when the transaction is completed, to co-operate on evaluating and developing gas supply options in Brazil. -BG shares closed Monday at 1,263 pence valuing the company at GBP42.9 billion. -By Rory Gallivan, Dow Jones Newswires; 44-20-7842-9411; rory.gallivan@dowjones.com