Oil prices rise on Iran tensions, OPEC output cuts

Oil futures rose on Friday as tensions over Iran and an extension to output cuts by OPEC and its allies boosted prices, but mixed economic data limited the rally.

Brent crude futures settled at $64.23 a barrel, up 93 cents, or 1.47 percent. US West Texas Intermediate (WTI) settled at $57.51 a barrel, up 17 cents. The US market was closed on Thursday for a national holiday.

Both benchmarks were down for the week as concerns about a slowing global economy outweighed risks to supply. Brent recorded a 3.3 percent weekly loss and WTI shed roughly 1.8 percent.

The US-China trade war has dampened prospects of global economic growth and oil demand, but talks resume next week in a bid to resolve the deadlock.

The US Energy Information Administration reported on Wednesday a weekly decline of 1.1 million barrels in crude stocks, smaller than the 5 million barrel draw reported by the American Petroleum Institute and less than analysts had forecast.

The Organization of the Petroleum Exporting Countries and allied producers such as Russia, known as OPEC+, supported prices by extending their deal on supply cuts.

Tension in the Middle East also offered support, particularly to Brent. "Brent is pricing in more of the geopolitical risk than WTI," said Phil Flynn, an analyst at Price Futures Group in Chicago.

Iran threatened to capture a British ship after British forces seized an Iranian tanker in Gibraltar over accusations the ship was violating EU sanctions on Syria.

"If Britain does not release the Iranian oil tanker, it is the authorities' duty to seize a British oil tanker," a Revolutionary Guards Commander wrote on Twitter.

A Reuters survey found OPEC oil output sank to a new five-year low in June, as a rise in Saudi supply did not offset losses in Iran and Venezuela due to US sanctions and other outages elsewhere in the group.