Oil prices rose 1 percent on Monday, hitting a fresh 15-month high above $83 a barrel, supported by data showing China's crude oil imports surged by nearly 25 percent in December and as the US dollar weakened.
The prolonged cold snap in the US and Europe continued to boost demand for heating fuel, lending support to oil prices.
US crude for February delivery rose 67 cents to $83.42 a barrel by 0958 GMT, off an earlier peak of $83.67, the highest price since October 2008.
London Brent crude gained 60 cents to $81.97.
But oil is still 43 percent below its July 2008 high of more than $147 a barrel.
“The weak US dollar, cold weather and robust Chinese import data are all supporting oil today,” said Carsten Fritsch, oil analyst at Commerzbank in Frankfurt.
“At the moment the market is only looking at positive data, not negative numbers,” he added.
China, the world's second-largest energy consumer, imported over 20 million tonnes of crude for the first time ever in December, up almost a quarter from November, according to Customs data published on Sunday.
Asian equities rose to a 17-month high on Monday as a strong rebound in China's exports raised optimism about the region's economic outlook, while the dollar fell 0.53 percent against a basket of currencies.
A weaker US currency makes commodities priced against the dollar, like oil, cheaper for those holding other currencies.
Tensions in Nigeria's main oil producing region have removed some supplies from the market, supporting prices, and traders will be watching carefully for further developments.
Chevron said on Saturday it had been forced to shut down 20,000 barrels per day (bpd) of crude oil production in Nigeria, a day after security sources said gunmen had attacked a pipeline operated by the US firm.
Saudi Arabia, the world's top crude exporter, has kept February oil supply to major Asian buyers and one European major largely steady against January levels, as the kingdom takes the lead in sticking to OPEC supply cuts, industry sources said on Monday.
With little US economic data this week, corporate results will be carefully watched to gauge the state of recovery in the world's largest energy consumer.
US equities could be in for a bumpy ride this week as three major companies in the Dow Jones index kick off the quarterly earnings reporting season, with investors looking for reassurances on future profits.
