A criminal complaint has been filed against four senior employees of a Greek newspaper over a “despicable” headline about Turkey’s President Recep Tayyip Erdogan.

Erdogan's lawyer Huseyin Aydin filed the complaint about the derogatory headline run in Dimokratia on September 18.

A criminal complaint submitted to the Ankara prosecutor's office says the suspects are Manolis Kotakis, the author of the article, editors Andreas Kapsampelis and Yorgos Giatroudakis, and Editor-in-Chief Dimitris Rizoulis.

Turkey has urged Greece to bring to account those responsible for the "shameless" action. 

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'Moral collapse not limited to marginal segments'

Following the complaint, the prosecutors in the capital Ankara launched an investigation against the newspaper.

The complaint also underscored that Erdogan's photo was placed along the headline with insulting expressions in Turkish and English.

Turkish judicial authorities have authority over the defamation cases about the president abroad, the criminal complaint stated.

"Considering the silence of the Greek public, it is understood that this moral collapse is not limited to marginal segments," it said.

'A despicable act'

Swearing is the language of those who do not have a word to say or are incapable of speaking in a proper language, it added.

"Swearing is a great shame and a despicable act not for its interlocutor, but for those who say it," the complaint said, adding that the target of this despicable act was not only the president but the interest of the Turkish nation that Erdogan defends with determination in the eastern Mediterranean and the Aegean Sea.

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Mild Greek response 

The Greek Foreign Ministry had said on Friday freedom of expression was fully protected in the EU member country but added, "The use of offensive language is contrary to our country's political culture and can only be condemned."

The two NATO countries are already locked in a heated row over energy exploration in contested waters in the eastern Mediterranean, but both sides have shown willingness to de-escalate tensions and resume talks.