Oil prices fell on Tuesday, pushing crude benchmarks to their largest monthly decline in two years as OPEC's output appeared to reach a 2018 high in July.
U.S. West Texas Intermediate crude futures (WTI) ended Tuesday's session down $1.37, or 2 percent, at $68.76 a barrel, after rising more than 2 percent in the previous session.
September Brent crude futures fell 73 cents, or 1 percent, to $74.24 a barrel by 1:29 p.m. ET after rising nearly 1 percent on Monday. The September contract expires later on Tuesday and the more-active October contract was down $1.33 at $74.22.
For the month, WTI futures declined 7.3 percent, while Brent futures were set to drop 6.5 percent. Both benchmarks posted the biggest monthly decline since July 2016.