Oil prices fell on July 18 as traders shrugged off the impact of the attempted coup in Turkey and the market turned its attention to bearish fundamentals, while disruptions to crude exports in Libya lent prices some support.

Brent crude futures fell 36 cents to $47.25 a barrel by 6:31 a.m. CT (11:31 GMT), while U.S. crude futures were 31 cents lower at $45.64 a barrel.

Istanbul's Bosphorus Strait, a chokepoint for oil that handles about 3% of global shipments, mainly from Black Sea ports and the Caspian region, reopened on July 16 after closing for several hours after the failed coup the day before.

News that oil guards protesting over pay shut Libya's Hariga oil terminal on July 17 dampened hopes the country could boost its output significantly any time soon.

"Libya remains a wild card in the global oil market balance," SEB chief commodities analyst Bjarne Schieldrop said.

"This morning, however, an immediate revival in Libyan crude exports looks less daunting and might help to support crude prices slightly," Schieldrop said.

Saudi Arabia's energy minister said on July 17 the kingdom always reacts to oil market supply and demand and would continue to monitor crude markets for any developments.

The race among oil suppliers to meet the rise in demand for imports from China's independent refineries is heating up, with Iran supplying a 2-million-barrel cargo via trader Trafigura.

A report by Morgan Stanley raised concerns about the longer-term outlook for oil consumption as demand for petrochemicals rather than fuels such as diesel and gasoline is clouding the outlook for crude demand.

"Fundamental headwinds are growing, supply-demand rebalancing is likely still a mid-2017 event, but tail risks are admittedly large in both directions, as geopolitics add to uncertainty," the report said.

"A rapid rise of non-petroleum products is boosting total product demand, but this is unhelpful for crude oil. Based on the latest data, even our tepid 800,000 barrels per day growth estimate for global crude runs looks too high," the report said.

Oil market investors again cut their bullish bets on Brent to their lowest since February.

Data from the InterContinental Exchange on July 18 showed investors cut net long positions by 8,899 to 303,371 in the week to July 12, their lowest since Feb. 22.