A final investment decision for the megaproject in the Shtokman gas field is expected in December. The Shtokman field is located 550km offshore Russia in the Barents Sea.

The estimated price tag of development will be presented in next month to the investors.

It is believed to be one of the largest gas fields but the project has already been delayed. The partners in the Shtokman project - Norway's Statoil, France's Total and Russian gas export monopoly Gazprom - have delayed pipeline gas production from Shtokman until 2016 instead of the originally planned 2013.

It is expected to require some $15 billion of investment in its first phase alone, according to the BarentsObserver.

The field, which contains 3.9 trillion cubic metres of gas and 56 million tonnes of condensate, is 550 km offshore at a depth of 340 metres, was discovered by the Soviet Union in 1988 and its start-up has been repeatedly delayed due to problems with financing and the lack of transport infrastructure in place.