The initial agreement in which Russia's Gazprom held a controlling 51 percent stake and France's Total 25 percent in the consortium expired at the end of June with the three companies failing to agree on technical and financial plans to develop the massive gas field.
As it had stated it would do if the agreement lapsed, Statoil booked a charge of 2.1 billion kroner (286 million euros) which completely writes off the value of the stake, said spokesman Fredrik Norman.
"But we remain in discussions with Gazprom with the goal of continuing this project in a profitable way," he told AFP.
Some analysts nevertheless said the move may signal a possible disengagement by Statoil from the technologically complex and expensive project as the company has other projects which would provide higher returns.
Statoil and Total were reported to have been unhappy with cost overruns and delays that hit the Gazprom-led venture -- a field discovered two decades ago but still untapped because of its forbidding environment in the Arctic.
Total has declined to comment on the future of Shtokman's development except to signal its continued interest.
Gazprom said the makeup of the consortium to develop the Barents Sea field it believes holds enough natural gas to supply the world for a year would not be decided before September.
Russian news reports said Royal Dutch Shell may join the project.