Some 13 Turkish warplanes violated Greek airspace 30 times in total on Tuesday (25 February), the Greek foreign ministry has said.

Two Turkish F-16 jets also did it twice on Monday, in what is becoming an ever more frequent event.

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There were 4,627 such incidents last year - an all-time high - the Greek ministry told EUobserver on Wednesday. There were also 3,705 violations in 2018 and 3,317 in 2017, it said.

Greece usually scrambles its own jets to escort Turkish ones out again.

The incidents are not likely to lead to a military clash, but they contribute to bad will in the region.

And they show Turkey's military adventurism in the air, amid other violations at sea, as well as interventions on the ground in Libya and Syria.

"Almost every week, we have these provocative actions from Turkish fighter planes," a Greek diplomat told this website on Wednesday.

"Greek planes do not violate Turkish airspace" in return, he added.

The Turkish foreign ministry could not be reached for comment.

But its website said Greek "abuse" of 1950s and 1930s aviation accords accounted for most of the "technical" violations.

The Greek line amounted to a "claim of de facto sovereignty over the whole Aegean airspace," the Turkish website said.

It was implausible that Greece and Turkey, who were Nato allies, would ever go to war over the issue, Pieter Wezeman, from the Stockholm International Peace Research Institute (Sipri), a Swedish think-tank, noted.

But there was a risk that air acrobatics could cause a fatal accident, he said.

And there was enough bad will already for Greece and its ally Cyprus to be spending heavily on arms despite ongoing economic hardship in the wake of Europe's financial crisis, he added.

"Greece spends more on certain kinds of weapons than would normally be expected from a Nato country of its size," Wezeman said.

"The security challenges we're dealing with in our wider region, including ... the behaviour of our neighbouring country Turkey, force us to upgrade our level of readiness," Greek defence minister Nikolaos Panagiotopoulos also said on Monday.

"This effort, of course, also has a financial impact," he said.

Greece recently hired a US firm to upgrade its F-16 fighter jets for €1.4bn.

It was in talks with France to buy two warships for €1.5bn in a deal expected to come through in a matter of "weeks", the Greek diplomat told EUobserver.

And Cyprus has bought €240m of anti-aircraft and anti-ship missiles also from France.

The Turkish air violations come amid Turkish naval incursions in Cyprus' waters and declarations on redrawing maritime borders in the Mediterranean.

They also come after Turkey sent troops to fight in Libya and Syria, in a sign of vaulting ambition.

French frigates

For her part, French defence minister Florence Parly was in Athens with Panagiotopoulos on Monday, when the two Turkish F-16s buzzed over the Greek island of Agathonissi.

She criticised Turkey for gas drilling in Cypriot waters and encouraged Greece to buy the €1.5bn French frigates.

"These peak technology vessels will allow Greece to significantly reinforce the deterrence capabilities that it needs in the Mediterranean," she said.

France also issued licences for sale of €530m of ammunition to Greece in recent times, the latest EU records showed.

And it issued permits for €160m of aviation parts and electronics.

But EU and Nato allies do business with both sides in the Aegean 'Cold War'.

France also issued licences for €220m of ammunition and €430m of military components to Turkey, while Spain is hoping to sell €1.1bn of transport aircraft to Ankara, the EU records indicated.