Oil futures edged up on Wednesday as worries that rising tensions in the Middle East could hit global supplies overshadowed an unexpected build in U.S. crude inventories. Brent crude gained 58 cents to $71.82 a barrel by 1:06 p.m. EDT (1706 GMT). U.S. West Texas Intermediate (WTI) crude futures climbed 25 cents to $62.03 a barrel. U.S. crude stocks rose unexpectedly last week to their highest since September 2017, while gasoline stockpiles decreased more than forecast, the Energy Information Administration (EIA) said. Crude stocks swelled by 5.4 million barrels, surprising analysts who had expected a decrease of 800,000 barrels. "Although crude oil inventories built more than the market expected due to higher imports, prices remained supported due to the geopolitical dynamics of the Middle East," said Andrew Lipow, president of Lipow Oil Associates in Houston. Also read:\u00a0Global markets-US, European shares strengthen after Trump auto-tariff delay Oil prices have drawn support since Saudi Arabia said on Tuesday that armed drones struck two oil pumping stations, two days after the sabotage of oil tankers near the United Arab Emirates. "Given that nearly one-third of global oil production and nearly all of global spare capacity are in the Middle East, the oil market is very sensitive to any attacks on oil infrastructure in this region," Swiss bank UBS said, adding it expected Brent prices to rise toward $75 in coming weeks. The attacks took place against a backdrop of U.S.-Iranian tension. Washington has been trying to cut Iran's oil exports to zero with sanctions while beefing up the U.S. military presence in the Gulf. Washington ordered the departure of non-emergency American employees from its diplomatic missions in Iraq on Wednesday in show of concern about threats from Iran-backed forces. "There could be a pretty serious conflict with Iran should they do something to U.S. forces in the region, and that would spike the price of oil," said Josh Graves, senior commodities strategist at RJO Futures in Chicago. "I think the oil traders of the world are looking at that and say, 'OK, what is the potential disruption there?'" Weak economic data from the United States and China capped prices by fuelling worries that global crude demand could slow. The International Energy Agency revised its forecast for 2019 growth in global oil demand 90,000 barrels per day lower to 1.3 million bpd. The energy watchdog also said the world would require very little extra oil from the Organization of the Petroleum Exporting Countries this year as booming U.S. output will offset falling exports from Iran and Venezuela.