Turkish President Recep Tayyip Erdogan announced on Friday that Turkey discovered its biggest ever natural gas field holding 320 billion cubic metres (11.3 trillion cubic feet) in the Black Sea, and more could be found as the country works to provide it by as soon as 2023.
If the gas can be commercially extracted, the discovery could help Ankara cut its current dependence on imports - from countries such as Russia, Iran and Azerbaijan - for a substantial amount of its energy needs.
"Turkey has realised the biggest natural gas find of its history in the Black Sea," Erdogan said, adding Ankara aims to become a net energy exporter.
The Fatih drill ship began work late last month in the Tuna-1 zone, about 100 nautical miles north of the Turkish coast in the western Black Sea.
All tests and engineering work has been completed, Erdogan said.
"This reserve is actually part of a much bigger source. God willing, much more will come. As a country that depended on the outside for gas for years, we look to the future with more security now," he said.
"There will be no stopping until we become a net exporter in energy."