MOSCOW, June 27 (Reuters) - Russia's Rosneft ROSN.MM , the world's top listed oil producer by volumes, plans to open a trading office in Singapore, Chief Executive Igor Sechin said in an article published in Izvestia newspaper on Tuesday.
He added that if oil prices stay at $40 per barrel for a prolonged time, half of global oil production would become loss-making, including in Brazil and Canada, with shale oil producers also likely facing "difficulties".