Oil prices have tumbled more than 2 per cent, notching the biggest weekly decline in more than a month on mounting evidence that US production and inventory growth were offsetting OPEC's attempts to reduce the global crude glut.
Oil prices have tumbled more than 2 per cent, notching the biggest weekly decline in more than a month on mounting evidence that US production and inventory growth were offsetting OPEC's attempts to reduce the global crude glut.