''Bulgaria has opened negotiations with Azerbaijan on the supply of additional quantities of natural gas to be used by the future gas distribution hub near Varna'', said Deputy Energy Minister Zhecho Stankov, reported BNR.

The two countries currently have an agreement on the delivery of 1 billion cubic metres of gas as of 2020.

The negotiations on extra quantities of gas will be conducted by the state companies Bulgartransgaz and SOCAR.