Crude oil futures gained more than $1 after Bernanke said that the Fed is committed to keeping interest rates extremely low for "an extended period."

The 4 percent spike was the largest percentage gain since late September.

Peak oil must serve as an "alarm that we need to take more seriously" by diversifying Saudi Arabia's economy, Mohammed al-Sabban said.

Crude oil closed nine cents lower at $67.96 amid high supply by OPEC and low demand by Americans.

Crude oil futures traded at levels that haven't been reached since November, after a government report showed that crude inventories gained significantly less than expected.