CNN  — 

French President Emmanuel Macron is rarely one to shy away from taking a selfie with the crowds or sharing a high-five, but there is one informality he won’t tolerate – nicknames.

Macron was on an official outing in Paris on Monday when he was greeted by one teenager with a “How’s it going, Manu?”

The too-friendly nature of the greeting clearly left Macron perturbed, leading him to promptly chastise the boy in a scene captured on camera and shared across social media, including by the President himself.

“No, you can’t do that, no, no, no, no,” Macron told the boy, who was lined up to meet the head of state during his visit to Mont Valerien fort, where hundreds of members of the French Resistance were executed during World War II.

“Sorry, Mr. President,” the teenager said, but that did not save him from being lectured by Macron.

“You’re here, at an official ceremony and you should behave. You can play the fool but today it’s the ‘Marseillaise,’ the ‘Chant des Partisans’ [French Resistance song], so you call me ‘Mister President’ or ‘sir.’ OK? There you go.”

The teen was then admonished for singing the Socialist anthem, the “Internationale,” in an attempt to criticize Macron’s pro-business reforms.

Macron added: “The day you want to start a revolution you study first in order to obtain a degree and feed yourself, OK? And then you can lecture others,” he said.