French far-right leader Marine Le Pen has been charged with misusing European Parliament funds relating to the payment of parliamentary aides.
The prosecutor's office said Le Pen was handed preliminary charges of breach of trust and complicity in breach of trust concerning two of her aides when she served at the European Parliament.
She was elected to the French parliament this month so gave up her seat in the European Parliament.
One of the aides in question, Catherine Griset, a senior aide at Le Pen's National Front party, was charged in February in the case.
Le Pen is suspected of using parliamentary funds to pay Ms Griset from 2009 to 2016 and bodyguard Thierry Legier from 2014 to 2016 for working as aides in Strasbourg, seat of the European Parliament, even though they have clear roles in her far-right National Front party.
Le Pen is also charged with complicity in breach of trust in her role as president of the National Front from 2014 to 2016.
Investigators suspect some National Front lawmakers used legislative aides for the party's political activities while they were on the European Parliament payroll. Griset was charged for allegedly receiving money through a breach of trust.
Le Pen denies the charges and plans to file at the Appeals Court on Monday demanding that the preliminary charges be annulled due to "the violation of the principle of separation of powers", her lawyer, Rodolphe Bosselut, said in a statement.
She will also seek a suspension of the investigation.
His reference to "separation of powers" may relate to a contention that the French justice system should not interfere in political party affairs.
Other European parliamentarians, including Le Pen's father Jean-Marie Le Pen and her companion Louis Aliot, have also been on the radar of the European investigative body OLAF for allegedly misusing parliamentary aides' wages.
Le Pen had twice refused summonses from authorities while campaigning, first for the French presidential election which she lost on May 7 to Emmanuel Macron, then for a lawmaker's seat in the French National Assembly which she won on June 18.