Analysts said the attacks have heightened uncertainties around the Middle East, and it was speculated they could be linked to the recent explosion of violence in the Middle East between Palestinians and Israel.
U.S. companies were unable to trade on the New York Mercantile Exchange, which closed after the attacks, and made their purchases through London's International Petroleum Exchange. The New York Mercantile Exchange is located within blocks of the World Trade Center.
The attacks presented no immediate threat to world oil supplies, analysts said, but professional crude oil dealers said traders had been forced into the market because of the uncertainty surrounding the terrorist attacks, and because commodities present a safe haven for jittery investors.
OPEC Secretary-General Ali Rodriguez said that the Arab-dominated cartel would ensure world oil supplies and price stability. Rodriguez said OPEC countries had substantial spare production capacity and were prepared to use it in order to achieve their goals.
"We are committed to promises to guarantee sufficient oil supplies and the policy of strengthening market stability," Rodriguez said after the attacks, adding that cartel members would not threaten to use oil as an economic weapon. "Furthermore OPEC's members are prepared to use their spare capacity, if deemed necessary, to achieve these goals."
