After being rejected by several countries, especially Egypt, the reaction came from Athens, which announced the expulsion of the Libyan ambassador, and gave him 72 hours to leave the country.
Greece described the Tripoli-Ankara agreement as "a flagrant violation of the (UN) law of the sea and the sovereign rights of Greece and other countries."
"The text of the agreement bears the signature of the Libyan foreign minister. He is the same person who assured the Greek side the opposite in September," said Greek Foreign Minister Nikos Dendias.
"The (geographical) coordinates of this attempt to demarcate the maritime boundary confirm that this agreement is a flagrant violation of the (United Nations) Law of the Sea and the sovereign rights of Greece and other countries," he said.
Turkey and the internationally recognized Libyan government have concluded a maritime border demarcation agreement and an agreement to expand security and military cooperation, a move Turkey said it was protecting its rights.
Greece responded immediately and called the agreement illogical because it ignored the existence of Crete between the coasts of Libya and Turkey.
Egypt and Cyprus have voiced opposition to the deal.