decreased oil prices, in the beginning of August trading, after four consecutive monthly gains, but slowing growth in China, and investor fears about the spread of the Delta virus, in addition to escalating tensions between Iran and the United States, were all pressure factors on crude prices.
West Texas Intermediate, on Monday, fell about 1%, after rising 2.6% last week.
Global crude markets are preparing this August to receive the production increase approved by the "OPEC +" alliance of 400,000 barrels per day.
Chinese economic activity continued to decline in July, implying a slower recovery this half of the year as growth risks mount, across the Asia-Pacific region, amid the spread of the highly contagious delta virus.
China has seen a slight increase in the number of coronavirus infections, Thailand is preparing to expand semi-closure measures, and infections in Sydney have matched a record.
While crude futures have fallen, traders are also watching rising tensions between Iran and the United States, Washington has formally blamed Tehran for an attack on an oil tanker linked to Israel, warning that it has the right to "respond appropriately."
The confrontation comes as the two countries seek to revive a nuclear agreement that could pave the way - if successful - to end US sanctions on official Iranian oil flows.