French judges have asked the European Parliament to lift Marine Le Pen's immunity so that she could face possible prosecution over misuse of parliamentary funds.
The far-right politician, among the leading candidates in the first round of France's presidential election on April 23, is accused of paying Front National aides up to €340,000 (£290,000) from EU funds while carrying out domestic party activity.
However, as a European Parliament member, Le Pen has immunity from prosecution.
Judicial sources have confirmed to Reuters and AP that a request to lift immunity has been submitted to the European parliament through the French government on Friday (14 April).
Appearing on French national TV, Le Pen said the claims were unfounded but declined to comment further.
In an earlier case, the European Parliament voted to revoke Le Pen's immunity for allegedly breaking French anti-terror laws after she tweeted three graphic images of Isis executions on Twitter.
According to French law, distribution of violent images or images which incite terrorism is banned. Those found guilty can be sentenced to up to three years in prison and a fine of as much as €75,000.
The developments have come at the tail-end of a week that saw Le Pen deny that the French state was responsible for its involvement in the Holocaust.
Le Pen was referring to an event known as the Rafle du Vel D'Hiv in which French police, at the request of the Nazi German authorities, rounded up 13,000 Jews from occupied and free France and deported them to German concentration camps.
In 1995, former President Jacques Chirac made a landmark apology and admitted the responsibility of the French state. The country's current president, François Hollande, has also expressed sorrow for the role of the French police during the event.
Following Le Pen's comments, her party's Parisian headquarters were the target of an arson attack by anti-fascist group Kombattre La Xénophobie (Fight Xenophobia).