Oil prices seesawed today as markets were lifted by hopes the US and China may resolve their trade disputes soon.
However they were then weighed down by a report Washington had granted several countries waivers on Iran sanctions.
Brent crude futures were at $72.88 per barrel this morning, a cent below their last close. They first fell today on surging supplies, before rising with global markets and then dipping again on the back of the reported Iran sanctions waivers.
US West Texas Intermediate (WTI) crude futures were down 33 cents, or 0.5%, at $63.36 a barrel.
Global markets, including oil, were lifted earlier by hopes that the trade dispute between the world's two biggest economies could be resolved soon.
Pulling crude back down, however, was a report that several governments had received waivers that would still allow countries to import some Iranian crude once US sanctions are reimposed from next week.
The US government has agreed to let eight countries, including close allies South Korea and Japan, as well as India, keep buying Iranian oil aid the upcoming sanctions, Bloomberg reported, citing a US official.
A Chinese official told Reuters that discussions with the US government were ongoing and that a result was expected over the next couple of days.
A list of all countries getting waivers is expected to be released officially on Monday, several briefed industry sources said.
Despite these efforts, analysts said any potential Iranian oil sanction waivers would likely only be temporary.
Goldman Sachs said it expects Iran's crude oil exports to fall to 1.15 million bpd by the end of the year, down from around 2.5 million bpd in mid-2018.
"We still expect that the global oil market will be in deficit in 4Q18," the bank said.
By the end of 2019, however, Goldman expects Brent to fall to $65 a barrel, largely due to "the unleashing of Permian (US shale) supply growth once new pipelines come online."