The development ministers of Bulgaria and Greece, Valentin Tserovski and Dimitris Sioufas, signed the document together with Russian Industry and Energy Minister Viktor Khristenko at a ceremony in Sofia.
Ministri razvitka Bugarske i Grčke Valentin Tserovski i Dimitris Sioufas, potpisali su dokument zajedno s ruskim ministrom industrije i energetike Viktorom Khristenkom na ceremoniji održanoj u Sofiji.