Brent was being pressured by expectations for higher Saudi and Russian Federation production, which impacts Europe and Asia, where Brent is the benchmark, more than markets dominated by US crude prices.
In addition to cutting prices, Saudi Arabia told OPEC it pumped about 10.5 million barrels of crude a day last month as the kingdom sought to cap rallying prices by ramping up output, according to people familiar with the matter.
Brent for September settlement lost 20 cents, or 0.2 per cent, to US$78.04 a barrel on the London-based ICE Futures Europe exchange, after gaining 48 cents on Wednesday.
Spare capacity, especially from OPEC countries, is an important measure by analysts to determine major oil exporters' ability to respond to rising demand. Rising gasoline prices could create a political headache for Trump before the November mid-term congressional elections by offsetting Republican claims that his tax cuts and rollbacks of federal regulations have helped boost the US economy.
In the global context, however, United States gas is already incredibly cheap.More news: LeBron: ‘Thank you Northeast Ohio for an incredible 4 seasons’
"This is business, Mr. President - we thought you knew it", he added.
Goldman Sachs said the market will stay in deficit in the second half of the year as actual and potential supply losses from Iran, Venezuela, Libya and Canada far exceed the proposed boost from OPEC and its partners.
South Korea is reported to have stopped importing Iran's oil and condensate in what appears to be a temporary halt until the country obtains an exemption from USA curbs on buying Iranian oil.
"Just spoke to King Salman of Saudi Arabia and explained to him that, because of the turmoil & disfunction (sic) in Iran and Venezuela, I am asking that Saudi Arabia increase oil production, maybe up to 2,000,000 barrels, to make up the difference..."
Energy consultancy FGE this week issued a stark warning of looming supply shortages due to United States sanctions against Iran and also because of disruptions elsewhere. OPEC has not defined oil prices for the past 30 years. Additionally, about 300,000 bpd of Libyan oil has been taken off the market.