Crude oil prices surged to a record high in the UK, amid reports that the US is considering military options in the nuclear row with Iran.
UK benchmark Brent futures settled $1.57 higher at $68.86 a barrel, after hitting a peak of $68.93.
New York light sweet crude futures gained $1.36 to close at $68.75.
Washington has rejected a media report that it is preparing for a military strike on Iranian nuclear facilities.
In the UK, prices have now breached previous record peaks of $68.89 dollars hit during 2005's storms.
Experts said almost all of Monday's gains were down to fears surrounding the oil-rich nation which could disrupt crude supplies.
"We might go up and test $70," said ABN Amro broker Lee Fader said, but he did add that significant supply disruption would be needed to push prices higher than the key $70 level.
