Oil prices surged nearly 20% at one point on Monday, with Brent crude posting its biggest intraday gain since the Gulf War in 1991, after an attack on Saudi Arabian oil facilities at the weekend halved the kingdom's production.
Prices came off their peaks after U.S. President Donald Trump authorized the use of his country's emergency stockpile to ensure stable supply.
Brent crude futures, the international benchmark, rose as much as 19.5% to $71.95 per barrel, the biggest intraday jump since Jan. 14, 1991. By 1100 GMT, the contract was at $65.38, up $5.16, or 8.6%.
U.S. West Texas Intermediate (WTI) futures climbed as much as 15.5% to $63.34, the biggest intraday percentage gain since June 22, 1998. The contract was later at $59.36, up $4.51 or 8.22%.
Saudi Arabia is the world's biggest oil exporter.
The attack on state-owned producer Saudi Aramco's crude-processing facilities at Abqaiq and Khurais cut output by 5.7 million barrels per day. The company has not given a timeline for the resumption of full output.