The move is likely to reignite tensions with Greece over the sovereignty of waters in the eastern Mediterranean and ownership of natural resources.
Erdogan made the announcement on Friday. The plan is for it to be functional by 2023, the centenary of the Turkish Republic.
A source in the presidential palace has told Euronews' Turkish service that President Erdogan will be announcing the discovery of a new natural gas source in the Mediterranean on Friday.
Greek foreign minister Nikos Dendias has visited Benghazi, the seat of Libya's eastern administration that is opposed to the UN-backed government.