President of French far-right Front National (FN) party Marine Le Pen delivers a speech during a rally in Lyon, France.

French judicial police are questioning far-right presidential candidate Marine Le Pen's bodyguard and chief of staff in relation to a probe into alleged misuse of European Union funds to pay parliamentary assistants, her lawyer said on Wednesday.

Marcel Ceccaldi told Reuters that the affair was a "manipulation" aimed at destabilizing the National Front's election campaign. Le Pen has previously denied any wrongdoing.