Crude oil prices rose during the day following data showing a decline in U.S. crude inventories and a move towards the activation of sanctions against Iran to raise expectations of tightening supplies as Russia warns of a fragile global oil market.
U.S. crude oil hit its highest level since Sept. 4 at $ 70.11 a barrel before retreating to 69.80 again, while Brent crude hit its highest level since May 24 at $ 79.63 a barrel before returning to the 79.20 level.
U.S. crude inventories fell by 8.6 million barrels to 395.9 million barrels by the week ending Sept. 7, according to data from the U.S. Petroleum Institute. Today, government data on crude oil inventories will be released from the Energy Information Administration.
Outside the U.S. investors are focusing on the impact of sanctions against Iran, which will target Iran's oil exports, and the United States is pressing several governments to cut imports of Iranian oil.
Alexander Novak, Russia's energy minister, warned of the impact of those sanctions and added that if prices spike, Russia could raise its output and have the capacity to increase production by 300,000 bpd.
