U.S. oil prices fell Friday as U. S. and Russia had \"constructive conversations\" on Syria issues. Traders kept a keen eye on the discussions held in Geneva, Switzerland, regarding a plan for Syria to surrender its chemical weapons. U.S. Secretary of State John Kerry said after initial meetings with Russian Foreign Minister Sergei Lavrov, \"We would both agree that we had constructive conversations.\" On the economic front, U.S. retail and food services sales for August edged up 0.2 percent to 426.6 billion U.S. dollars from the previous month, the Commerce Department said. Economists had generally expected a gain of 0.4 percent. Meanwhile, the U.S. Producer Price Index for finished goods rose 0.3 percent in August on a seasonally adjusted basis, the Labor Department reported. Meanwhile, prices for finished goods excluding foods and energy were unchanged in August. The Thomson Reuters/University of Michigan preliminary index of consumer sentiment for September dropped to 76.8 from 82.1 last month. The figure was below market expectations and hit the lowest level since April. The market also expected that the U.S. Federal Reserve will begin to scale back its monthly asset purchases program on its monetary policy meeting next week. Light, sweet crude for October delivery moved down 39 cents to settle at 108.21 dollars a barrel on the New York Mercantile Exchange. Brent crude for October delivery climbed 15 cents to close at 112.78 dollars a barrel