Turkish President Tayyip Erdogan called on Monday for Turks to boycott French goods and urged European Union leaders to halt French leader Emmanuel Macron's "anti-Islam" agenda.
For a third day running Erdogan said that the French president needed a mental health check, repeating a rebuke that caused France to recall its ambassador from Ankara over the weekend, as he appealed to Turks to shun French products.
"Just like they say 'Don't buy good with Turkish brands' in France, I am calling to all my citizens from here to never help French brands or buy them," Erdogan said.
France is the 10th biggest source of imports into Turkey and the seventh biggest market for Turkey's exports, according to Turkey's statistical institute. Among major French imports, French autos are among the highest selling cars in Turkey.
Shares in the Turkish unit of French-American telecoms equipment company Alcatel Lucent ALCTL.IS were down 10% on the Istanbul stock exchange after Erdogan's comments.
"European leaders with foresight and morals must break down the walls of fear," Erdogan said in a speech at the start of a week of activities in Turkey to commemorate the birthday of the Prophet Mohammad.
"They must put an end to the anti-Islam agenda and hate campaign that Macron is leading."
Macron has pledged to fight "Islamist separatism", saying it was threatening to take over some Muslim communities in France. The country has since been shaken by the beheading of a teacher by an Islamist militant, avenging the use of cartoons of the Prophet Mohammad in a class on freedom of expression.
Turkey and France are both members of the NATO military alliance, but have been at odds over issues including Syria and Libya, maritime jurisdiction in the eastern Mediterranean, and the conflict in Nagorno-Karabakh.