An attack on Saudi Arabia on Saturday night, which knocked out more than half of Saudi Arabia's oil production and damaged the world's biggest crude processing plant, triggered the biggest jump in oil prices in almost 30 years.
Oil prices surged by as much as 19% before coming off their peaks. The intraday jump was the biggest since the 1990-91 Gulf crisis over Iraq's invasion of Kuwait.
The market eased from its peak after Trump announced that he would release US emergency supplies and producers said there were enough stocks stored up worldwide to make up for the shortfall. Prices were around 12% higher by 1645 GMT.
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