US crude for August delivery fell 65 cents to $ 73.50 a barrel after rising 8 percent last week, according to Reuters.

Brent crude fell 55 cents to $ 78.68 after rising more than 5 percent last week.

The White House said on Saturday that the Saudi king had promised Trump that the kingdom would increase oil production if necessary and that it had the capacity to produce an additional 2 million barrels per day.

Trump attacked the Organization of the Petroleum Exporting Countries (OPEC), pointing to the need to stop manipulating the world oil markets and intensified pressure on Washington's allies close to the threat of sanctions on European companies dealing with Iran./