KIEV, June 24 – Naftogaz Ukrayiny still believes that the conditions of the gas transit contract of 2009 signed with Russia's Gazprom are discriminatory and the company will continue achieving its revision via negotiations, but if the talks are a failure, the company will file a claim at the Stockholm arbitration institution, Naftogaz Ukrayiny Chairman Andriy Kobolev said.

"I think that we'll try to settle the issue [the transit contract] via talks. If they are a failure, then we'll go to the Stockholm arbitration institution," he said.

He found it difficult to predict when the issue could go to court, adding the procedure for filing a suit at the arbitration institution for this contract differs from the procedure for the contract on gas supplies that Ukraine recently used in its dispute with Gazprom on the price of gas.