The president of the oil producers' group, Opec, has warned that crude prices could rise further this week if eurozone interest rates go up.
Dr Chakib Khelil told the BBC that he expected a rise in rates to lead to a further weakening of the dollar which would push oil prices higher.
Dr Khelil blamed the fall in the value of the dollar for recent record highs.
He also rejected calls to increase the supply of oil, saying a boost by Saudi Arabia had failed to temper prices.
"What happened was that instead of coming down, they increased, because the perception of the market is that the dollar will continue weakening in future," Dr Khelil told the BBC's World Business Report at the Petroleum Congress in Madrid.
The price of oil hit another record level last week, when US light, sweet crude traded at $143.67 a barrel.
In late morning trading in London, Brent crude was up almost $1 at $141.58
