sanctions on Iran and falling Venezuelan output limited the decline.

Benchmark Brent crude oil fell 35 cents to settle at $77.42 a barrel. U.S. crude slipped 45 cents to settle at $69.80.

Brent closed the month 4.3 percent higher while U.S. crude gained 1.5 percent. Oil has been buoyed by tumbling Venezuelan output and declining shipments from Iran ahead of the imposition of U.S. sanctions on Tehran in November.

On Friday, however, oil "appears to be following equities lower amidst renewed U.S./Chinese tariff concerns that could easily escalate in slowing global economic growth and, hence, world oil demand," Jim Ritterbusch, president of Ritterbusch and Associates, said in a note.

The MSCI Emerging Markets index fell for a second day as a report that U.S. President Donald Trump was preparing to step up a trade war with Beijing dampened risk appetite and erased some gains from a rally this week. In the previous session, concerns about Argentina's currency weakening weighed on the outlook for emerging markets.

Trump threatened on Thursday to withdraw from the World Trade Organization and impose tariffs on $200 billion of Chinese imports.

The U.S. rig count, an indicator of future production, rose for the first time in 3 weeks, energy services firm Baker Hughes reported.

U.S. crude oil rig flanges gulf coast production in June hit 10.674 million barrels per day, the highest monthly total on record, the Energy Information Administration (EIA) said in a monthly report on Friday.

Crude exports rose nearly 200,000 bpd in the month, hitting a new record of 2.2 million bpd, more than twice last June's level, the EIA said in a separate monthly report on Friday.

U.S. crude's discount to Brent <WTCLc1-LCOc1>, which has widened by nearly a third in the past month, has encouraged an increase in U.S. exports, said Bob Yawger, director of energy futures at Mizuho.

Production from the Organization of the Petroleum Exporting Countries increased by 220,000 bpd in August, according to a Reuters survey.

Oil analysts polled by Reuters cut their price forecasts for 2018 in August, for the first time in almost a year, on growing trade concerns. A Reuters survey of 45 economists and analysts forecast Brent would average $72.71 in 2018, 16 cents below the $72.87 projected in July but above the $71.96 average so far this year.

Speculators raised their bullish bets on crude for the first time in more than a month, U.S. Commodity Futures Trading Commission data showed on Friday.

(Additional reporting by Christopher Johnson in London and Henning Gloystein in Singapore; editing by David Gregorio and Phil Berlowitz)