LONDON: Oil prices extended losses on Thursday after a rise in US commercial crude reserves, while traders turned cautious before this weekend’s crunch producers’ meeting. A warning by the Organisation of the Petroleum Exporting Countries (OPEC) that the world remains oversupplied also dampened sentiment as key producer nations prepared to gather in Doha for Sunday’s talks on freezing output. At about 1030 GMT, US benchmark West Texas Intermediate for delivery in May was down nine cents at $41.67 a barrel. Brent North Sea crude for June delivery dipped 11 cents to $44.07 a barrel compared with Wednesday’s close.