The first stage of the ambitious project, which is controlled by Russian gas export monopoly Gazprom, will cost $15 billion though partners will be able to initially finance part of it, Yuri Komarov told reporters.
"We will begin intense talks with banks this year ... The founders understand that initially funding will come from our own capital," Komarov said.
Exact investment figures for the project, in which France's Total has a 25 percent stake and Norway's StatoilHydro 24 percent, will be available in the first quarter of next year, he added.
Norway's Foreign Minister Jonas Gahr Stoere told Reuters in an interview on Wednesday that Shtokman investment will not be linked to a dispute between Norway's Telenor and Russia's Alfa Group for control of Russian telecom operator Vimpelcom
Shtokman has recoverable reserves of 3.8 trillion cubic metres in the stormy Barents Sea, making it one of the world's biggest gas fields.
Gas production is expected to begin in 2013, while liquefied natural gas (LNG) will start a year later.
