Brent oil’s front-month May contract lost 0.85 percent at $54.85 a barrel after it previously closed up 89 cents, or 4 percent, at $55.32 a barrel.
Front-month US WTI crude for May was down 1.25 percent at $45.99 a barrel. April contract, which expired on Friday, settled up $1.76, or 1.6 percent, at $45.72.
Jonathan Barratt, the chief investment officer at Ayers Alliance Securities in Sydney, told Bloomberg that the current price volatility means the oil market may face a further downturn in the short run.
Saudi oil minister Ali al-Naimi said on Sunday that the country would keep up its daily oil production at 10 million barrels and, as the world’s top petroleum exporter, was ready to accommodate the needs of just about any potential buyer.