Turkey is reportedly threatening to delay the ratification of North Macedonia’s NATO accession protocol if the Balkan country does not extradite 15 Turkish nationals Ankara accuses of taking part in a failed coup in 2016, Kathimerini reports.

According to the newspaper, Ankara insists that the 15 Turkish nationals are members of a network run by self-exiled cleric Fethullah Gulen, who it says masterminded the coup attempt.

Following the signing of the Prespes agreement with Greece in June last year, NATO member-states’ permanent representatives signed a protocol on the accession of North Macedonia to the alliance in February this year. But Ankara’s threat could now stall North Macedonia’s bid to join the North Atlantic alliance. The issue was also raised by Turkish Defense Minister Hulusi Akar during his visit to Skopje on April 3. During a recent visit to neighboring Kosovo Akar made extradition requests for other Turkish nationals also accused of being Gulenists, the Greek newspaper said.

North Macedonia’s Prime Minister Zoran Zaev has rebuffed Ankara’s demands and has received backing from European Union officials, who also called on the government in Skopje to uphold the human rights of the 15 men. However, North Macedonia’s Defense Minister Radmila Sekerinska said during a recent television interview that, apart from other members of the North Atlantic alliance, her country also needs Turkey for the ratification of its NATO accession protocol, Kathimerini writes.

Ankara has been ratcheting up tensions with Athens since 2016 with regard to the fate of eight servicemen that Turkey accuses of participating in the coup who have been granted asylum in Greece.

In February of this year, Turkey’s state-run Anadolu news agency reported that the government in Ankara was offering a total of 5.6 million euros for the return of the eight officers.