On Oct. 26, Greece named a consortium of France's Total, Hellenic Petroleum--its biggest oil refiner--and Italy's Edison as the preferred bidder for an offshore gas drilling block in the west of the country.

In 2015, Athens tendered 20 offshore blocks in the Ionian Sea, and south of the island of Crete, for deepsea oil and gas drilling. These offers were unsealed in February.

The Total-led consortium bid for one block in the Ionian Sea, while Hellenic Petroleum bid independently for two other blocks. A committee assessing the bids will invite the consortium to finalize the contract, the country's energy ministry said in a statement.

Hellenic Petroleum, in a venture with Edison, and sole oil producer Energean Oil, are already searching for oil in three onshore and offshore blocks in western Greece.

Greece, which signed up to a third bailout last summer, has made several fruitless attempts over the last 50 years to find large oil and gas reserves. Its debt crisis, and important resource finds in neighboring countries, prompted Greece to step up those efforts.