Total SA's (TOT) chief executive Thursday said the key question before it finalizes approval for its planned investment in Russia's Shtokman offshore gas project would be whether it's economical.

Total SA's (TOT) chief executive Thursday said the key question before it finalizes approval for its planned investment in Russia's Shtokman offshore gas project would be whether it's economical.

Speaking at a presentation to analysts to discuss earnings and outlook, Christophe de Margerie said it's unlikely Total will have cause to change its longer-term outlook for oil prices, to which the price of natural gas is linked. He also said it's unlikely Total wouldn't be able to afford to participate.

But if the French oil major were to deem the cost of the project above $80 a barrel, then it might have cause to pull out of the development or to delay, restructure or make it smaller, he said.

Russian gas monopoly OAO Gazprom (OGZPY) owns 51% of the giant Shtokman Development, a joint venture with Total, which owns a 25% stake, and Norway's StatoilHydro ASA (STO), which owns the remaining 24%.