LONDON (Bloomberg) — The supply of supertankers competing to haul two million-barrel cargoes of Middle East crude oil jumped to a seven-month high as demand faded.

The surplus of very large crude carriers, or VLCCs, seeking cargoes over the next 30 days rose to 35 percent, according to the median estimate of four brokers and one owner surveyed by Bloomberg News yesterday. That's up from 28 percent a week ago to the highest since July 20.

Rental income from shipping Saudi Arabian crude to Japan, the industry's benchmark supertanker route, last week slid 44 percent to $26,770 a day, according to the London-based Baltic Exchange. That's less than the $32,900 that Bermuda-based Frontline Ltd., the biggest operator of the vessels, said in November it needs to break even on them.

Last week the surplus increased more than threefold, the most since Bloomberg began collating the data in March 2009. As of July 20 of last year, the surplus was 40 percent.