Investing.com - Oil prices extended losses from the prior session on Monday, after the U.S rig count rose for the first time since December, renewing worries of a supply glut. U.S. crude shed 30 cents, or 0.73%, to $40.84, by 9:50GMT. Brent crude lost 14 cents, or 0.34%, at $41.05 a barrel.Baker Hughes said Friday that the number of rigs drilling for oil in the U.S. increased by one last week to 387, ending three straight months of weekly declines.The renewed gain in U.S. drilling activity fueled speculation that domestic production could be on the verge of rebounding in the weeks ahead.