SOFIA- Bulgaria's natural gas bourse operator Balkan Gas Hub has picked Trayport, a London-based unit of Canada's TMX Group, to provide it with an exchange trading system, it said on Monday.

As part of plans to transform Bulgaria from a transit country for Russian gas into an energy trading centre, Balkan Gas Hub has teamed up with the Vienna-based Central European Gas Hub to set up a gas trading operation at the Black Sea city of Varna. It is expected to begin at the start of 2020. 

Bulgaria's first liquid physical and gas trading hub will initially introduce over-the-counter and exchange contracts tailored for the Bulgarian market, the company said in a statement.

State gas wholeseller Bulgargaz will provide the first gas for trading, which is expected to amount to about 7% of the country's total annual gas consumption next year, gradually rising to 35%. Bulgaria's gas consumption is about 3 billion cubic meters of gas per year.

The first auction for deliveries in 2020 will be held on December 9 and potential participants can register until December 4.

Bulgaria, which currently gets almost all of its gas from Russia's Gazprom, is building a gas link with neighbouring Greece that should allow the import of Azeri gas, as well as LNG deliveries, from 2021.

(Reporting by Tsvetelia Tsolova; Editing by Kirsten Donovan) ((tsvetelia.tsolova@thomsonreuters.com; +359-2-93-99-731;))