The office of Turkish President Recep Tayyip Erdogan said that he discussed in a phone call with his US counterpart Donald Trump on Wednesday bilateral and regional issues, including the tension in the waters of the Mediterranean.

Tensions have escalated between Turkey and Greece since Ankara sent the survey vessel "Oroch President" to disputed waters in the eastern Mediterranean this month in a move that Athens described as illegal.

There are severe differences between Turkey and Greece, the two members of NATO, over the sovereignty of oil and gas resources in the region, based on differing views on the extension of the continental shelf of each of the two countries in the waters that are spread by mostly Greek islands.

Erdogan's office said in a statement that the Turkish president made clear during the call that his country "was not the party that creates instability in the eastern Mediterranean," and that Turkey "has demonstrated its support for dialogue and de-escalation by taking concrete steps."

Earlier Wednesday, the Secretary-General of the United Nations, Antonio Guterres, called for the need to reduce tension in the eastern Mediterranean and resolve differences between the countries concerned in accordance with the UN Charter, while Germany condemned the military maneuvers in the region.

The UN Secretary-General’s call came during Guterres’s spokesman, Stephane Dujarric, responding to journalists ’questions about the Secretary-General’s position on the Greek Ministry of Defense’s announcement - on Tuesday - of joint military exercises south of the eastern Mediterranean island of Crete, with Cyprus, Italy and France, between Tuesday and Friday.

Dujarric said during a press conference, "We are clearly following these developments in the eastern Mediterranean (...) and with the presence of this number of parties involved, as you know, there are various military forces and maneuvers taking place ... therefore we urge all concerned parties to dialogue."

He added, "Those parties must resolve their differences based on the principles stipulated in the (UN) Charter."

German denouncement

For its part, German Defense Minister Annegret Kramp Karnbauer condemned - on Wednesday - the opposing military maneuvers taking place in the eastern Mediterranean, saying that they "do not help" to reduce tension between Turkey and Greece in this region.

Germany, which holds the presidency of the European Union in the second half of 2020, is currently carrying out a mediation mission between Athens and Ankara.

Within the current manifestations of escalation in the Mediterranean waters, Greece said that it intends to extend the western border of its territorial waters in the Ionian Sea (one of the branches of the Mediterranean), amid a very escalating crisis in the Mediterranean waters, and a Turkish warning against the consequences of "mistakes that may lead to the destruction of some countries."

On Wednesday, Greek Prime Minister Kyriakos Mitsotakis confirmed that his country intends to extend the western limit of its territorial waters in the Ionian Sea to 12 miles.

"Greece will expand its western territorial waters to 12 nautical miles from 6 miles," he told MPs during a debate on whether parliament would approve a recently reached agreement on the maritime border between Greece and Italy.

Joint military exercises

In the same context, the Greek Ministry of Defense announced the start of joint military exercises with France, Italy and Cyprus in the eastern Mediterranean, from today until next Friday.

French Minister of the Armed Forces, Florence Parly, said that the eastern Mediterranean is turning into a space for tensions, and that respect for international law should be the rule, not the exception.

The minister indicated that her country, with its Cypriot, Greek and Italian partners, will begin a military exercise, starting from Wednesday, by air and sea means.

She added that her country's message is simple, which is that the priority is dialogue, cooperation and diplomacy in order for the eastern Mediterranean to be a space for stability and respect for international law, and not a field for the aspirations of some.

Meanwhile, the Turkish Ministry of Defense said that it continues to train its naval forces with its counterparts of the allied countries.

According to a tweet by the Turkish Ministry of Defense published on its Twitter account, on Wednesday, the frigate Barbaros and another warship conducted naval exercises with the US destroyer "Winston Churchill" in the eastern Mediterranean.