SARAJEVO - Bosnia's major gas importer Energoinvest said on Wednesday it has extended a deal on gas supplies with Russia's Gazprom until the end of the year under unchanged conditions.

Energoinvest said it signed an annex to its contract with Gazprom on Tuesday, under which the price for gas will be corrected on a quarterly basis as was already the case, based on the nine-month change in the price of oil derivatives.

"The signing of this annex enables a continued free supplying of the Federation of Bosnia-Herzegovina with natural gas until Jan. 1 2023, when the signing of the new annex of the contract is scheduled," the company said in a statement.

Bosnia is made up of the Federation dominated by Bosniaks and Croats and the Serb-dominated Serb Republic, with the former the main gas consumer.

Energoinvest General Manager Bisera Hadzialjevic said that Gazprom had not demanded changed currency terms from Bosnia, which pays in euros, but added that she expected gas prices to rise in the third quarter.

In April, the Federation government increased the price of natural gas for the second quarter by 21.7% following a price rise by Gazprom.

The Balkan country has no reserves of gas, which accounts for up to 8% of its energy use.

It relies on Russian supply for around 400 million cubic metres of gas per year and has been receiving gas from Gazprom since the start of 2021 via the TurkStream pipeline and a new route crossing Turkey and Bulgaria.

(Reporting by Daria Sito-Sucic; editing by Jason Neely)