The claim is in an Instagram post featuring two images: a black-and-white image of a shirtless young man and a recent photo of President Emmanuel Macron's 71-year-old wife. Both faces look similar.

“Bridgitte Macron is a Man,” the image overlay text said.

The post caption added: "The entire Olympics opening ceremony makes sense".

A reverse image search of the image of the young man revealed it to be a modified version of an image of a model on a stock photo website.

The body of the young man pictured was identical to the image in the post, with the same pose, contours, and hand placement.

However, the man in the Instagram image had a different head and a chest tattoo.

The distinct marks on the wall above the man’s left shoulder and right ear were also identical to those in the Instagram image.

The image and claim have also been viewed millions of times after being posted on X, formerly Twitter, by a French-speaking user.

Similar falsehoods about Ms Macron have circulated since at least 2021, originally spread by far-right French websites, the BBC reported.

Many of the false claims say she was born as a male named Jean-Michel, which the letters of the tattoo superimposed on the altered Instagram image spell.

French court is due to rule in September in the trial of two women accused of making false claims about Ms Macron on YouTube in 2021, Le Monde reported. 

Similar false claims that other prominent female political figures, such as Michelle Obama and Jacinda Ardern, were transgender have been debunked by PolitiFact and The Spinoff NZ.