British gas and oil producer BG Group said it had agreed to sell its Brazilian gas distribution business Comgas to Cosan for $1.8 billion as it unveiled soaring first quarter profits on the back of higher oil prices and production.

BG is selling its controlling stake in Comgas to focus resources on developing major finds in Brazil and elsewhere. Upstream oil production activities are traditionally more profitable than downstream businesses.

The company reported a 55% rise in underlying profits to $1.27 billion, in line with analyst forecasts.

BG said production rose 5% in the quarter compared to the same period in 2011, to 670,000 barrels of oil equivalent per day.

BG's result compares to falling output at rivals BP, Chevron and ExxonMobil.