Oil prices slipped into the red on Friday after the International Energy Agency (IEA) cut its outlook for oil demand growth in 2019, saying economic sentiment is weakening and the consequences for oil demand are becoming apparent.
Benchmark Brent crude for August delivery eased 0.6 percent to $60.95 a barrel, after rising 2.2 percent in the previous session.
West Texas Intermediate crude futures for July delivery were down 0.7 percent at $51.92 a barrel, after climbing 2.2 percent on Thursday in the wake of attacks on two oil tankers in the Gulf of Oman.
The IEA revised down its 2019 demand growth estimate by 100,000 barrels to 1.2 million barrels per day (bpd), but said it would climb to 1.4 million bpd for 2020.
Meanwhile, U.S. Secretary of State, Mike Pompeo, accused Iran of orchestrating a series of attacks on tankers in the Strait of Hormuz, though Iran denied any involvement.
"These unprovoked attacks present a clear threat to international security, a blatant assault on the freedom of navigation, and an unacceptable campaign of escalating tension by Iran," Pompeo told reporters.
The U.S. military has released a video showing what it claimed was Iran's Revolutionary Guard removing an unexploded limpet mine from one of the oil tankers targeted near the key waterway.
In another development, OPEC and other producers including Russia are in final talks for an agreement, that may be signed in early July, to cooperate on oil supplies on a long-term basis, Japan's Nikkei reported.