Oil prices tumbled more than 2 percent on Monday in volatile trade, as the dollar strengthened and China posted weak domestic demand data, sinking prices that had gotten a short-lived boost on concerns about potential reductions in crude supply from Libya.
U.S. West Texas Intermediate (WTI) crude futures ended Monday's session down $1.23, or 2.5 percent, at a three-week low of $47.59 a barrel. Global benchmark Brent crude futures were down $1.36, or 2.6 percent, at $50.74 a barrel by 2:29 p.m. ET (1829 GMT).
Trade was volatile, with prices falling early on the Chinese demand data, then retracing losses after Libya's national oil corporation said it was investigating security violations at the country's largest oil field.
Chinese refineries processed 10.71 million barrels per day (bpd) in July, National Bureau of Statistics (NBS) data showed, down around 500,000 bpd from June and the lowest rate since September 2016.
Analysts said the drop was steeper than expected, exacerbating concerns that a glut of refined fuel products could weaken Chinese demand for oil.