Oil prices edged up on Monday after top exporters Saudi Arabia and Russia said they would stick to extra voluntary oil output cuts until the end of the year, keeping supply tight, while investors watched out for tougher U.S. sanctions on Iranian oil. Brent crude futures rose 41 cents, or 0.5 per cent, to $85.30 a barrel by 0000 GMT while U.S. West Texas Intermediate crude was at $81.05 a barrel, up 54 cents, or 0.7 per cent. In line with analysts' expectations, Saudi Arabia confirmed it would continue with its additional voluntary cut of 1 million barrels per day (bpd) translating into a production of around 9 ... (full story)