South-east Europe’s gas market is moving through one of its most important structural changes since the first post-Ukraine-war diversification push. The region is no longer simply replacing Russian gas with alternative molecules. It is building a multi-directional supply map in which Greek LNG, Croatian LNG, Romanian offshore gas, Azerbaijani supply, Turkish transit capacity and new interconnectors are starting to define the commercial hierarchy of the market.
The clearest signal comes from Greece, where Atlantic SEE LNG Trade, the joint venture between AKTOR Group and DEPA Commercial, has doubled its long-term supply agreement with Venture Global from 0.5mn tonnes per year to 1mn tonnes per year, equivalent to about 1.3 bcm of gas annually, for 20 years from 2030. This is not just a supply contract. It is a commercial claim over the future of the Vertical Corridor, using Alexandroupolis LNG and Greek infrastructure to push US LNG north into Bulgaria, Romania, Serbia, Hungary and other markets that remain exposed to supply volatility.
Albania is entering the same structure from a different direction. AKTOR LNG USA and ALBGAZ signed a 20-year, $6bn deal for US LNG supplies, with Albania expected to receive around 1 bcm per year from 2030. Until Albania develops its own import capacity, gas is expected to arrive through Revythousa, Greece’s national gas network and the Trans Adriatic Pipeline. That gives Greece a near-term infrastructure role and gives Albania a contractual position in the regional gas market before it becomes a fully mature gas consumer.
Croatia is also tightening its position. Its LNG terminal capacity has expanded from 2.9 bcm/year to 6.1 bcm/year, while pipeline capacity toward Hungary is set to rise to 3.5 bcm/year and toward Slovenia to 1.5 bcm/year. Zagreb is turning Krk and the connected pipeline system into a north-western SEE supply platform, serving Hungary, Slovenia and Bosnia and Herzegovina.
Romania may become the region’s production anchor. The Neptun Deep project, developed by OMV Petrom and Romgaz, could help Romania become a significant net gas exporter by 2028, with surplus production exceeding domestic demand by more than 60 TWh/year and possible export availability of up to 5 bcm/year. Serbia’s planned gas interconnection with Romania places Belgrade directly inside that future supply equation.
The market implication is blunt: SEE gas is becoming a corridor business. Value will accrue not only to producers and suppliers, but to companies controlling regasification, storage, pipeline access, balancing rights and cross-border capacity. AKTOR, DEPA Commercial, Venture Global, SOCAR, BOTAS, Bulgargaz, OMV Petrom, Romgaz, Plinacro and MOL now sit in the same strategic picture. The next phase of SEE gas competition will be decided by which corridors can provide predictable volume, bankable contracts and lower political interruption risk.








