Brent oil futures have moved into backwardation, analysts JBC said Friday, a move that could trigger a release of floating inventories to the market.

The Vienna-based energy consultancy said the contracts closest to delivery were now trading higher than those expiring later, a phenomenon known to traders as "backwardation".

Traders tend to store oil offshore hoping to capture higher prices in subsequent months compared with current ones, a trend called "contango".

The Organization of Petroleum Exporting Countries warned in its November report that "the shrinking contango will likely trigger a release of crude oil from floating storage." It said: "the current level of calendar spreads are unlikely to be profitable for holding crude oil on vessels considering the cost of storage."

By Benoit Faucon, Dow Jones Newswires; +44 77 601 777 36; Benoit.Faucon@DowJones.com