Oil prices soared on Tuesday as the weak dollar hit a record low against the euro - tempting more investors towards commodities as an alternative.
Oil has now reached $98.62 a barrel for the second time.
US light, sweet crude touched a record-equalling $98.68 a barrel before settling up $3.39 at $98.03 a barrel.
London Brent crude also enjoyed a spurt, adding $3.21 to $95.49.
Tight supplies, winter demand and ongoing geopolitical concerns have also contributed to oil prices climbing by about 45% since August.
Some observers say that $100-a-barrel oil is now inevitable.
Adjusting for inflation, US light crude's record peak of $101.70 came in 1980 against a backdrop of war between Iraq and Iran.
Analysts examining minutes from the Federal Reserve's latest rate-setting meeting, released on Tuesday, said there was a good chance that there would be another interest rate cut in December.
This would be expected to weaken the dollar further as commodities and other currencies and became more attractive to investors they said, forcing up oil prices
"Expectations of interest rate cuts by the Federal Reserve are sending the dollar lower and this is once again drawing buyers... into the crude oil market," said TFS Energy Futures Addison Armstrong.
Oil prices had already risen on Monday, after leaders of producers' cartel Opec decided not to increase production at their latest meeting.
Traders will be carefully watching Wednesday's weekly crude inventory data, released in the US by the Energy Information Administration.