PARIS - Fighting "Islamist terrorism" is France's top foreign policy priority, President Emmanuel Macron said Tuesday, vowing to make his country a leading power in an unstable, increasingly polarised world.

"Providing security for our citizens means that the fight against Islamist terrorism is our first priority," Macron told some 200 French diplomats gathered in Paris. "There's no place for naivete, nor for fear of Islam that confuses Islamism and Islamic," he said, adding that assuring the security of the French was the "raison d'etre" of the country's diplomacy.

Since early 2015, France has suffered a series of terror attacks that have claimed more than 230 lives, making it the country worst affected in western Europe. Macron said he would work with the various powerbrokers in the Middle East to try eradicate the jihadist threat.

 "Some have chosen (their camp). It's a mistake. The strength of our diplomacy is to speak to all sides," he said.

France will host a conference on cutting off sources of funding for terror groups like Islamic State in early 2018, he added.

The 39-year-old leader also insisted there was no alternative to the 2015 nuclear deal with Iran, which has been fiercely opposed by US President Donald Trump.