Trump once again called on OPEC countries to do more to bring down crude prices and linked US foreign policy to his demand, saying the USA defends some oil producing countries "for very little" money.
Trump's scramble to slow down the oil rally comes four months ahead of U.S. midterms, where analysts say rising gasoline prices could hurt Republicans.
In a tweet on Saturday, Mr Trump said Saudi Arabia had agreed to increase oil output by up to two million barrels.
An imminent shift in global oil trade flows was also affecting prices.
Output cuts by OPEC and allies since January 2017 have reduced a crude glut.
Yet despite Riyadh voicing support for Trump, Saudi Arabia may find it tough to compensate for future losses from Iran and persistent supply disruptions from Libya and Venezuela.
Saudi Arabia told OPEC it pumped about 10.5 MMbopd last month as the kingdom sought to cap rallying prices by ramping up output, according to people familiar with the matter.
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He can not be put in to referee a match of this magnitude". "Respect, fair play and joy for the game is all that matters tonight". England will have just three days to recover before facing Sweden in Samara on Saturday for a place in the semifinals.
The global benchmark slipped 23 cents, or 0.3%, to US$78.01 a barrel at 2:05pm in London.
FXTM analyst Lukman Otunuga said at the time that prices received a "solid boost" from the Trump administration's decision to cut off all imports of Iranian oil in November. US crude CLc1 slipped 43 cents to $72.51.
Foreign ministers from the five remaining signatories of a nuclear deal between Tehran and world powers will meet Iranian officials in the Austrian capital to discuss how to keep the accord alive after the US withdrawal from the pact.
While Saudi Arabia is facing mounting pressure from Trump to do more, America's oil sanctions on Iran and trade frictions with China are adding to uncertainties as the planned USA tariffs on Chinese goods are set to start on Friday.
The recent strength in oil prices has, in part, been spurred by a U.S. announcement that it plans to re-introduce sanctions against Iran, Opec's third-largest producer, from November, targeting oil exports.
USA and Saudi objectives are not fully aligned, however, on oil prices.
OPEC and Russian Federation said in June they were willing to raise output to address concerns of supply shortages due to unplanned disruptions from Venezuela to Libya.
Spare capacity, especially from OPEC countries, is an important measure by analysts to determine major oil exporters' ability to respond to rising demand.
Yesterday, the deputy commander of the Sarollah Revolutionary Guards in Tehran warned that any attempt to undermine Iran's oil exports will lead to the closing of the Strait of Hormuz-a narrow waterway vital to oil distribution in the Persian Gulf region.