Brigitte Macron has denied claims that she is a long-standing supporter of Nicolas Sarkozy after the former conservative president reportedly revealed that France's first lady had "voted for him all her life".
The claim is embarrassing for France's current president, Emmanuel Macron, 39, who was elected in May on a "neither Right nor Left" platform but has since faced criticism from the Left that his reform agenda is decidedly Right-wing.
On Friday his government is due to pass a landmark reform of France's labour code that sparked a day of nationwide strike protests earlier this month. One Leftist leader called it a "social coup d'état".
Mr Sarkozy, 62, who was Right-wing president of France from 2007 to 2012 before losing to Socialist François Hollande, was cited in Sunday's Journal du Dimanche newspaper as saying he had learnt of his unlikely political fan at a dinner at the Elysée Palace in July.
At the end of the meal, also attended by his wife Carla Bruni-Sarkozy, Mr Sarkozy reportedly exclaimed: "(Brigitte Macron) is great! She told me she had voted for me all her life!"
Regarding Mr Macron he would only say: "I get the impression he's very lonely."
However, according to RTL radio, Mrs Macron, 64, has vigorously denied any suggestions she is a closet Sarkozy supporter, exclaiming: "I have never told anyone for whom I vote, and will never tell anyone.
"The ballot box is the ballot box!"
Mrs Macron's denial came as her husband waxed lyrical about the power of "love" for political leaders.
"Love is part of my life and my balance. I do believe you don’t build something great and you don’t behave properly if you are not balanced as a strong couple," he told CNN in an interview in New York before a speech to the United Nations.
"I’ve been with my wife for a decade now, and she is part of me.”
Earlier this month, Mrs Macron was cited as confessing to being "scared stiff" at the prospect of being France's first lady and unsure if she was up to the job in a book charting her husband's rise to power this year.
But this week, Philippe Besson the author of a Character from a Novel, who is a friend of the Macrons, said she was now enjoying the role.
"Now that's she's doing the job, I think she's really flourishing," he told TV chat show C à vous.
He said she appeared happier in the post than many of her predecessors. "That said," he added, "she's in love with her husband so that makes things different from previous situations we've known."
Mr Sarkozy's second wife, Cécilia, ran off with another man just after he was elected president. Mr Hollande was revealed to having secret trysts with actress Julie Gayet a stone's throw from the Elysée while his official girlfriend, Valérie Trierweiler, was still ensconced in the presidential palace.
Mrs Macron, a former teacher who married Mr Macron in 2007, accompanied her husband to New York.
Unlike Mr Hollande, who publicly slammed his erstwhile protégé in August for seeking to impose “useless sacrifices” on French workers, Mr Sarkozy has never openly criticised Mr Macron.
Shortly after his landslide election victory in May, Mr Sarkozy said the president deserved to be called a “genius” if he managed to successfully implement his radical reform agenda before the end of his five-year term.