The President and his wife arrived at the fort in Bormes-les-Mimosas (Var, Provence-Alpes-Côte d'Azur) on Friday afternoon, and welcomed British Prime Minister Theresa May for an official visit that evening.
In a statement, the Elysée Palace confirmed that a drone had later been spotted flying above the fort, and said: “An inquiry is underway concerning this flyover."
The statement did not confirm or deny whether the drone in question had been shot down or recovered.
It continued: “The majority of stays [at the fort] by the President are private and unofficial”, and said that “the outings of the President are completely private”.
Drones are remotely-controlled, small, unmanned aircraft that can be piloted from afar, and often carry equipment such as cameras or lasers.
While they have a number of legitimate uses, they are often seen as problematic around sites such as private properties, airports and prisons.
Despite the issue, the couple is expected to stay at the fort for two weeks, as originally planned.
Apart from the visit from Mrs May, neither the President nor his wife has been seen publicly since arriving at the fort.
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