Turkey’s embassy in Washington has announced Turkish vessel Oruc Reis has started searching for oil and gas in the Eastern Mediterranean.

In a lengthy tweet thread, the Turkish Embassy seeks to debunk Greece’s assertion that the island of Kastellorizo, near which the research is taking place, has a continental shelf.

Many countries, including Greece, dispute Turkey’s interpretation.

On Thursday, US Ambassador to Greece Geoffrey Pyatt reiterated the US view that islands have “exactly the same” continental shelf and exclusive economic zone rights as does any mainland territory.

“I have also made a point on many occasions and I will make it again today, that the United States adheres to the principal of international maritime law that islands, including Kastellorizo,” Pyatt told state news agency ANA