The quip “OK, boomer" is discriminatory and reinforces “ageism”, has warned the author of a French government-commissioned report on finding ways to bridge the growing generation gap.

The term went viral last month after a 25-year-old New Zealand MP used it to dismiss an older heckler during a speech about climate change.

Young people now use it on social media as a way of brushing off the views of "baby boomers" perceived to be out-of-touch, condescending or closed-minded.

Dubbed the youthful riposte to “snowflake millennial”, it has struck a nerve with one US radio host declaring the phrase to be “the n-word of ageism”. According to the New York Times, it marks “the end of friendly generational relations”.

In France, there have been a string of attempted translations, including the arguably cruel: “D’accord, presque mort” (OK, one foot in the grave).

That may explain why Gallic politicians have failed to see the funny side of the tongue-in-cheek put-down of scolding oldies.