london (Bloomberg) — Bermuda-based Frontline Ltd., the world's biggest owner of supertankers, said oil traders want to charter as many as 10 vessels to stockpile crude to take advantage of higher prices later in the year.

About 25 supertankers were already hired for storage and there are enquiries for five to ten more, Jens Martin Jensen, Singapore-based interim chief executive officer of the company's management unit, said by phone.

The traders would buy crude now and sell it for delivery later, profiting from a futures market situation called contango where prices are higher as the year progresses. The vessels could handle as much as 20 million barrels, or about what is produced by OPEC member Algeria in 15 days. They would add to as much as 50 million barrels already hoarded at sea, for a combined amount equal to almost five days of European Union demand.

"I've never before seen storage demand on this scale," said Didier Labat, a Paris-based shipbroker at Barry Rogliano Salles who has worked in tanker markets for about 20 years.

Commodities prices fell the most in five decades last year, with crude dropping more than $100 from the peak of $147.27 a barrel in July, as simultaneous recessions hit the US, Europe and Japan. Oil demand in 2008 fell for the first time since 1983, according to the Paris-based International Energy Agency.

Thirty-five supertankers represent about seven percent of the global fleet of very large crude carriers, according to data from London-based Drewry Shipping Consultants Ltd. Storing oil in tankers may buoy rental rates that fell by a record 78 percent last year as slower economic growth sapped demand for energy.

Traders are seeking to lease ships for three to nine months, Jensen said. Crude oil for December delivery traded at $61.90 a barrel as of 10.49 a.m. in London, $13.66 more than the February contract. Oil companies and traders may be able to profit from storing the oil, assuming shipping, insurance and financing costs are covered.

A supertanker would cost about 90 cents a barrel a month for storage depending on the length of the rental, according to data last month from shipbroker Galbraith's Ltd.

Iran, the second-largest member of the Organisation of Petroleum Exporting Countries after Saudi Arabia, idled as many as 15 of its biggest ships in May to store crude oil. That contributed to three consecutive months of higher rental rates for ships.

The cost of delivering Middle East oil to Asia, the world's busiest route for supertankers, rose yesterday for the first time since December 5, according to the Baltic Exchange in London.