The President of the Council of Europe on Saturday rejected a military coup attempt in Turkey late on Friday night.

“Any attempt to overthrow the democratically elected leaders in a member state of the Council of Europe is unacceptable,” Thorbjorn Jagland said on his Twitter account.

Jens Stoltenberg, NATO Secretary General, called for calm and restraint in Turkey, Anadolu Agency reported.

In a written statement on Saturday, Stoltenberg said he spoke to Turkish Foreign Minister Mevlut Cavusoglu.

“I call for calm and restraint, and full respect for Turkey’s democratic institutions and its constitution. Turkey is a valued NATO Ally,” he said.

EU foreign policy chief Federica Mogherini called for restraint and respect for democratic institutions in Turkey following the attempt.

Newly appointed British Foreign Minister Boris Johnson also voiced concern via Twitter and urged Britons in Turkey to follow the British Foreign and Commonwealth Office’s advice.