The offshore energy sector in Greece is preparing for a long-awaited revival as ExxonMobil, Energean, and Helleniq Energy Upstream sign a farm-in agreement for exploration in the northwestern Ionian Sea. The U.S. major will acquire a 60% stake in Block 2, reducing Energean’s participation from 75% to 30% and Helleniq Energy’s to 10%. Energean will remain operator during the exploration phase, while ExxonMobil will assume this role if commercial quantities of hydrocarbons are discovered.
Located close to the Italian Exclusive Economic Zone, Block 2 is considered the most advanced concession in Greece in terms of exploration readiness. Energean describes it as the largest unexplored offshore structure in the Mediterranean, with the potential to significantly boost the energy security of Greece and neighboring countries. The partners have already acquired and analyzed 2,244 square kilometers of 3D seismic data, identifying the Asopos structure as the primary target for drilling. Exploratory works are anticipated for late 2026 or early 2027, pending regulatory approvals and an extension of the exploration phase.
Dr. John Ardill, Vice President of Global Exploration at ExxonMobil, emphasized that the agreement “paves the way for potential future exploratory drilling investments in the 2027 timeframe,” underlining ExxonMobil’s commitment to safe and environmentally responsible exploration. Energean CEO Mathios Rigas described the development as a strategic milestone for Greece’s role on Europe’s energy map and an opportunity to “demonstrate that the country can responsibly use its domestic resources to achieve energy independence.”
For Romania and the wider regional gas market, the Ionian Sea project reinforces the emerging energy corridor that connects the Eastern Mediterranean with Southeast and Central Europe. As Romania develops its own Black Sea gas resources and infrastructure for LNG imports, Greece’s offshore prospects could become part of a broader regional framework aimed at reducing dependence on external suppliers and strengthening energy interconnections through the Vertical Gas Corridor. The convergence of exploration, LNG infrastructure, and pipeline projects across the region may gradually transform Southeastern Europe into a more integrated and resilient gas network.
If drilling proceeds as planned, the Ionian Sea operation would mark Greece’s first offshore exploration activity since 1981, when the Katakolo field was discovered — a historic return to offshore drilling that could redefine the country’s energy trajectory within the European context.