BERLIN — Turkey and Greece will join the European Sky Shield Initiative, bringing the total number of countries participating in the German-led initiative to 21.

The German, Greek and Turkish defense ministers announced the move on Feb. 15 at a Brussels summit of NATO defense ministers.

The European Sky Shield Initiative, ESSI, was launched in August 2022 by German chancellor Olaf Scholz. It seeks to streamline joint procurement of air defense capabilities across Europe and enhance the interoperability of systems.

The initiative is in response to a perceived European vulnerability against attacks of the kind Russia has launched on Ukrainian infrastructure.

German chancellor Scholz said in December 2022 that he hoped the plan would be fully developed within five years from that date. Half a year later, the German parliament authorized the nearly €4 billion ($4.3 billion) purchase of the Israeli Arrow-3 anti-ballistic missile system.

This week’s Hellenic-Turkish letter of intent comes just days after former U.S. president and presumptive Republican nominee for the November general election, Donald Trump, criticized NATO partners for not meeting the alliance’s spending goals.

“This initiative helps translate allied commitments on defense spending into tangible capabilities available for our collective defense,” said NATO Deputy Secretary-General Mircea Geoană. “It demonstrates the clear commitment of European allies to fair burden sharing as well.”

The ESSI architecture is separate from NATO and also includes neutral Austria and Switzerland, who together joined in mid-2023.

Turkish Defense Minister Yasar Guler called the accession an “important step towards fulfilling NATO’s necessities,” adding that Turkey was “ready to contribute to this initiative with our wide range of national resources.”

Turkey, a NATO member, has previously purchased the Russian-made S-400 air-defense weapon, raising questions about interoperability with other members of the Sky Shield Initiative.

Turkey has the second-largest army in NATO after the United States. The country has a longstanding rivalry and unresolved disputes with fellow alliance member Greece, particularly over demarcation lines in the Aegean Sea.

Linus Höller is a Europe correspondent for Defense News. He covers international security and military developments across the continent. Linus holds a degree in journalism, political science and international studies, and is currently pursuing a master’s in nonproliferation and terrorism studies.

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