New York: Oil prices suffered big losses as investors worried that Britain's exit from the European Union would slow the global economy. The West Texas Intermediate for August delivery on Tuesday dropped $2.39 to settle at $46.60 a barrel on the New York Mercantile Exchange, while Brent crude for September delivery plunged $2.14 to close at $47.96 a barrel on the London ICE Futures Exchange, Xinhua news agency reported. Meanwhile, signs of ample supplies also weighed on the market. Nigeria pumped an average of 1.53 million barrels per day in June, up about 90,000 a day from May, according to the Bloomberg survey. Productions in Saudi Arabia, the biggest crude exporter, rose by 70,000 barrels a day to 10.33 million last month, the survey showed.