On Tuesday, the embassies of Canada, Denmark, Finland, France, Germany, the Netherlands, New Zealand, Norway, Sweden, and the US made a joint appeal to release Kavala after four years under arrest.
On the same day, the ten ambassadors were summoned to the Turkish Foreign Ministry, and later Erdogan threatened to expel them from the country over the violation of the Vienna Convention on diplomatic relations.
"I instructed our Foreign Minister to immediately take measures to ensure that these ten ambassadors are declared personae non gratae," Erdogan said in a public address in the city of Eskisehir, broadcast on his Twitter.
Kavala is a well-known Turkish businessman and human rights activist. He is the founder of the Anadolu Kultur foundation, promoting ethnic and religious minority projects, particularly the reconciliation between the Turkish and Armenian people and the peaceful resolution of the Kurdish issue.
In February 2020, a Turkish court acquitted Kavala on the charge of ties to the anti-government Gezi Park protests in 2013. However, on the same day, the Istanbul prosecutor's office issued a new warrant which re-arrested Kavala on charges of ties to the failed 2016 coup. Kavala has denied all charges brought against him.