The political party led by French centrist politician Francois Bayrou has come under intense scrutiny following revelations that it may have abused European Parliament money.

A former member of Bayrou's Democratic Movement (Modem) testified before a prosecutor in Paris on Wednesday (7 June), in what French media are reporting is part of a broader probe into assistants unlawfully drawing salaries from the EU parliament under the 2009 to 2014 legislature.

Student or retired? Then this plan is for you.

News service France Info, which had spoken to the witness following the hearing, said the person had been contracted out as an assistant to a now former MEP, Jean-Luc Bennahmias, but never did any real work for him.

Instead, the person had worked for Bayrou's Modem, which would be against EU parliament rules, as the institution bans using EU tax payer money to finance national parties.

The person was allegedly receiving pay from the Democratic Movement and then drew a second salary from Bennahmias from January to December 2011, in what would amount to a fake job.

Bennahmias told French media that it is impossible to distinguish between European and domestic work inside the Democratic Movement "given that we are all specialists of Europe."

Modem's leader Bayrou, is justice minister under Emmanuel Macron and a key ally of the new president. He is preparing a new law to "moralise" French politics.

Two other Modem MEPs and now ministers could also be concerned by the new assistant case: defence minister Sylvue Goulard and EU affairs minister Marielle de Sarnez.

The revelations come just days before Sunday's first round of the legislative elections, where Macron, with Modem support, will try to obtain an absolute majority in the National Assembly, France's lower chamber.

France Info also cites numerous other MEPs by name, both current and former, as likely having used EU tax payer money to pay assistants based in France.

The apparent scam appears much bigger than just one case with Le Parisien, a French daily, saying over a dozen French MEPs, including from other political parties, are involved in a preliminary investigation into the abuse.

The scandal appears to be initially rooted in a book written by former MEP Corinne Lepage in 2015, where she had denounced the abuse.

The issue was then taken up by the far-right party, National Front, after it had itself been found to be illegally paying off assistants with EU parliament funds.

The EU parliament started last week to examine a request from French judges to strip National Front leader Marine Le Pen of her immunity, following revelations that some 20 assistants were listed as working at the party's headquarters in Paris.

A similar scandal had also surfaced during the French presidential campaign against Republicans leader Francois Fillon, who was charged with complicity in the abuse of public funds earlier in March.

The failed presidential contender, who had initially campaigned on the image of being scandal-free, had allegedly provided his wife and children with fake jobs paid by the French taxpayer.