Oil prices continued last week's sharp decline on Tuesday, triggered by expectations that Saudi Arabia and Russia could pump more crude to compensate for a potential supply shortfall.
Brent crude futures were down 70 cents, or nearly 1 percent, at $74.60 a barrel at 12:16 p.m. ET (1506 GMT), after settling on Monday at their lowest since May 8 at $75.30.
U.S. West Texas Intermediate (WTI) crude was down $1.91, or 2.8 percent, at $65.97 a barrel, sitting around its lowest since mid-April.
Brent crude now commands its largest premium over U.S. futures in more than three years, meaning that U.S. exports are rapidly becoming far more competitive globally than those from northern Europe, Russia or parts of the Middle East.