US oil prices fell to the lowest level in six months Wednesday as government report showed last week American crude inventories rose more than expected. The U.S. Energy Information Administration (EIA), the Energy Department's statistical arm, Wednesday released its report covering U.S. crude supplies of last week. U.S. crude stockpiles added 2.95 million barrels to 391.4 million barrels for the week ended Nov. 22, higher than market expectation for a 700,000 barrels rise. American refineries ran at 89.4 percent of total capacity, up 0. 8 percentage points from the prior week. U.S. crude production continues to climb as the new technology helps to exploit shale oil in the central part of the country. The increase of American oil supplies weighed on the market, especially the U.S. oil price. Iran reached an agreement with six world powers over its nuclear issue last Sunday and fueled expectations for rising oil supply in the future. Trader believed that more Iranian oil will return to international markets in the long term, the additional supply is likely to make oil prices less expensive. Light, sweet crude for January delivery lost 1.38 U.S. dollars to settle at 92.3 dollars a barrel on the New York Mercantile Exchange,while Brent crude for January delivery gained 43 cents to close at 111.31 dollars a barrel.