First lady cost a third of Carla: Hollande's girlfriend costs French taxpayers £36,000 a month less than Sarkozy's wife President's girlfriend Valerie Trierweiler's office costs £16,730 a month But former first lady Carla Bruni cost taxpayers £52,858 monthly French first lady Valerie Trierweiler costs the taxpayer three times less than former president Nicolas Sarkozy's wife Carla Bruni. Socialist president Francois Hollande's girlfriend has monthly "running costs" of £16,730 for her office and five staff at the Elysee Palace. But supermodel Miss Bruni ran up a £52,858 bill, with eight staff, and another team running her official website. Valerie Trierweiler (right) costs French taxpayers a third less a month than former first lady Carla Bruni (left) The figures emerged after right-wing MP Guillaume Larrive tabled a parliamentary question demanding to know how much France was spending on Miss Trierweiler. The answer was published on Prime Minister Jean-Marc Ayrault's website, but it added that "as a comparison," Carla Bruni cost three times more. Both Miss Trierweiler and Miss Bruni have been accused of excessive spending, with the present first lady even the target of an ongoing legal action for abusing public money. Supermarket chain heir Xavier Kemlin launched the highly unusual complaint, claiming the taxpayer should not be supporting her lifestyle as the "president's mistress." President Francois Hollande's girlfriend Valerie Trierweiler is currently the target of a bizarre legal action claiming she is abusing public money Former president Nicolas Sarkozy's wife Carla Bruni has been accused of being a 'fashion victim' like Marie Antoinette The court in Saint-Etienne is obliged to study Mr Kemlin's case before ruling on whether Miss Trierweiler should face prosecution, but experts say it has no chance of success. Three years ago, prominent Belgian historian Patrick Weber branded former catwalk model Bruni a "frivolous fashion victim who is isolated from reality." In his book called Queen Carla he said her love of high fashion and obsession with psychotherapy left her cut off from the French people. He wrote: 'She behaves like the former queens of France, who is consorting with her king after an arranged marriage. She is rich and Italian like Catherine de Medici, a follower of the arts like Anne of Brittany and a frivolous fashion victim like Marie-Antoinette.