CAIRO — Egypt and Greece on Thursday signed a maritime deal that sets the sea boundary between the two countries and demarcates an exclusive economic zone for oil and gas drilling rights.

The deal is a response to a similar agreement between Turkey and Libya’s Tripoli-based government last year that has spiked tensions in the East Mediterranean region. The Turkey-Libya deal was widely dismissed by Egypt, Cyprus and Greece as an infringement on their economic rights in the oil-rich sea. The European Union says it's a violation of intentional law that threatens stability in the region.

Greece and Turkey have been at odds for decades over sea boundaries but recent discoveries of natural gas and drilling plans across the east Mediterranean have exacerbated the dispute.

“This agreement allows Egypt and Greece each to move ahead with maximizing their benefits from resources available in this exclusive economic zone, namely promising oil and gas reserves,” said Egypt’s Foreign Minister Sameh Shukry after Thursday's brief signing ceremony in Cairo.

He added that “Egyptian-Greek relations have been crucial to maintaining security and stability in the East Mediterranean region and for countering threats caused by irresponsible policies that support extremism and terror,” a reference to Ankara's support for the Tripoli government.

In Libya's proxy war, Egypt has been on the opposite side from Turkey and has backed the rival administration based in eastern Libya and the east-based military commander Khalifa Hifter. Cairo claims Turkey is backing extremists on behalf of the U.N.-supported government in Tripoli.

With Turkish military support, the Tripoli government has repelled Hifter's 14-month-long military campaign to capture the Libyan capital. After Turkey turned the tide in the Libyan war, Egypt’s President Abdel Fattah el-Sissi threatened a military incursion into Libya, leading to concerns of a direct Egyptian-Turkish confrontation.

Greece's Foreign Minister Nikos Dendias hailed the Egypt-Greece deal as as “an exemplary agreement." However, neither minister revealed any details of the deal.

“It is the complete opposite of the illegal, invalid and legally non-existent memorandum of understanding between Turkey and Tripoli,” Dendias added.

Turkey argues that Greek islands should not be included in calculating maritime zones of economic interest — a position Greece says violates international law. Greece has around 6,000 islands and smaller islets in the Aegean and Ionian Seas, more than 200 of them inhabited.

Last month, the Greek government was alarmed by plans by Turkey to proceed with an oil-and-gas research mission south of Greek islands in the eastern Mediterranean.

FM Dendias in Cairo: Agreement with Egypt confirms the rights of our islands

Greece signed a historic agreement "delineating the maritime zones with Egypt," Greek Foreign Minister Nikos Dendias said in Cairo on Thursday, at a joint press conference with his counterpart Sameh Shoukry.

"Today's agreement confirms and guarantees the right and influence of our islands on the continental shelf and an Exclusive Economic Zone (EEZ)," Dendias explained, adding that Greek-Egyptian relations are entering a new phase of closer ties. The just and mutually beneficial agreement, he noted, is a model one and important for the entire East Mediterranean.

He also noted that it was drawn in the context of International Law and that it respects its provisions and those of the Law of the Sea. "It also respects good neighborhood relations, it contributes to stability and security in our region, and it resolves an old outstanding issue. It is an agreement between two friendly, neighboring countries that respect their histories," he said.

Dendias said the agreement also contrasts with the illegal and legally baseless memorandum of understanding between Turkey and the Tripoli government, and said the Greek-Egyptian agreement will relegate it to the dustbin, where it belonged from the start.

Greece, he underlined, with continue to move ahead with delineations with other countries it shares borders with, always respecting International Law and the Law of the Sea. He invited all such countries to follow the example of today's agreement and that which Greece signed recently with Italy.

Tsipras: Greece needs to pursue closer alliance with Egypt

Negotiating with Egypt on an exclusive economic zone (EEZ) is vital for Greece, because it will "break the illegal agreement between Turkey and the Sarraj government of Libya," main opposition SYRIZA leader Alexis Tsipras says in an interview with iefimerida, the second part of which will be released on Friday.

Tsipras says the contribution of a third ally of Greece like Egypt will help, but on the other hand "a bad agreement with Egypt could provide Turkey with ammunition in its claims against our territorial rights, as defined by international law."

He also says there is no question of talks on a package of issues, as Turkey wants, and there is no question of revising the Lausanne Treaty. There are no "gray zones" in the Aegean, nor can Greek-Turkish relations be linked to the Cyprus issue, the SYRIZA leader says in the interview published over two days, and calls for "the restart of exploratory talks for the delineation of the continental shelf and an EEZ, without threats or other agendas."