The five oil companies once told they were not needed are invited back to develop the giant Shtokman gas field in the Russian Barents Sea, Bloomberg news reported from Davos, Switzerland Friday.

The report said the Russians will call back Chevron, ConocoPhillips, Norsk Hydro, Statoil and Total to the 3.7-trillion-cubic-metre field.

"When we announced that we would develop the project ourselves, we meant that our reserves would 100% stay with Gazprom," Bloomberg quoted Gazprom deputy chief exec, Alexander Medvedev said.

In a recent merger undertaking by Norwegian heavyweights Statoil and Hydro, the oil companies cited a stronger technology offering for projects like Shtokman as one of the reasons for their union.

Tags: Shtokman