France's socialist president François Hollande has accused his spurned partner of lying in a book where she claims he despises the poor, in the latest twist of a love spat that has shaken the Elysee palace.

In an interview released a week after the first damaging extracts of Valérie Trierweiler's memoir Merci Pour Ce Moment ('Thank You for This Moment') were made public, Hollande denied he refers to the less wealthy with scorn, calling them "the toothless".

"I have lived this attack on the poor, the needy as a blow to my whole life," he told Le Nouvel Observateur.

"In all my offices I haven't thought of anything but helping and represent those who suffer. I've never been on the side of the powerful, although I'm not their enemy."

"Do you think I've forgotten where I come from?" Hollande asked, adding that his maternal grandfather was a small tailor who lived with his family in a modest apartment in Paris, while his paternal grandfather was a teacher from a poor peasant family in northern France.

Trierweiler's allegations of elitism came at a delicate political moment for Hollande, who has been openly accused by the most radical members of his party of betraying socialist campaign pledges that got him elected to pursue a pro-business agenda instead.

"He portrays himself as a man who does not like the rich. In reality, the president does not like the poor," Trierweiler wrote.

In another passage France's former first lady wrote that he expressed dislike for her working-class parents.

Trierweiler wrote the book in great secret in the months following her breakup with Hollande, which was sparked by revelations in the press that he was having an affair with actress Julie Gayet.

The first 200,000 copies were sold out within a few days from publication and so was the next stock of 100,000 that was specially printed to meet demand.