Turkey's foreign ministry says the area under demarcated in the deal is located in Turkish continental shelf, as reported to the United Nations.
Turkey has slammed a "so-called agreement" between Greece and Egypt on exclusive economic zones (EEZ) in the Eastern Mediterranean.
Stressing that Greece and Egypt had no mutual sea border, the Turkish Foreign Ministry declared in a statement on Thursday that the so-called maritime agreement was "null and void" for Ankara.
The so-called demarcated area is located on Turkey's continental shelf, as reported to the UN, the ministry added.
Turkey's continental shelf
It also noted that Egypt had already abandoned 11,500 square kilometres (3,350 square nautical miles) of its continental shelf with a previous agreement it signed with the Greek Cypriot administration in 2003.
Egypt is again losing its maritime jurisdiction with the latest so-called treaty, which seeks to usurp Libya's rights as well, it said.
Turkey will not allow any activity in these areas and will continue to resolutely defend its legitimate rights and interests in the Eastern Mediterranean, as well as those of the Turkish Republic of Northern Cyprus, added the statement.
Libya denounces deal
Libya also condemned the deal between Greece and Egypt.
“Libya will not allow violations of its maritime rights,” foreign ministry spokesman Mohammed Al Qablawi said on Twitter.
Al Qablawi reiterated Libya’s commitment to a memorandum of understanding concerning the delimitation of maritime jurisdiction signed with Turkey.
Libya also urged the states bordering the Mediterranean to act in accord with the principles of international law.
The prime minister of Greece maintains that the maritime deal signed with Egypt is “in accordance with international law.”
Greek PM Kyriakos Mitsotakis said the deal is “a legitimate agreement that fully satisfies both countries," but made no mention of Turkey or its proximity to the continental shelf throughout his statement.