Anti-fraud boss: EU parliament in 'too many' complaints

“Over the last year, the [Olaf] unit dealing with internal cases has been flooded with [allegations],” he said.

Kessler said that at the end of April, Olaf had 47 ongoing investigations that dealt with staff or officials of all EU institutions, “not only the parliament”.

But he noted that “most of them” involved investigations into MEPs, their assistants, or parliament staff.

Kessler would not comment on specific probes, or reveal the political affiliations of those under scrutiny, because Olaf never comments on ongoing cases.

“Also because there are so many, too many actually, that I don't even remember all of them,” Kessler said.

For around the past two years, Olaf has received allegations about MEPs' assistants being hired under false pretences.

In 2015, then president of the EU parliament Martin Schulz publicly accused some 20 assistants from the National Front, a French far-right party, of financial irregularities.

Last February, an Olaf report said a contract by the party's chief, Marine Le Pen, signed for her bodyguard could also constitute a "misappropriation of funds, or fraud and use of fraud".

“Then they reacted by reporting to us the situation of their colleagues,” Kessler said about Le Pen's party, Front National.

He said the allegations caused “tit-for-tat” reactions, a phrase he also used two years ago. But on Wednesday he said that such retaliatory accusations had occurred “also very recently”.

Kessler said he had addressed his concerns with the parliament.

“Maybe you have to better manage this issue of the assistants, which are paid by the European Parliament but supervised only by one MEP, the MEP of whom they are assistants. Maybe the system doesn't work,” he said.

“As far as I know, they have already started changing a bit the rules in order to leave less space for possible fraud or mismanagement,” said Kessler, noting the cooperation between the parliament and Olaf was good.

But he also noted that the issue of assistants fraud “should be addressed at a political level”.

“It's never good when you have investigators knocking at your door,” he said.

“When there are too many of these cases, maybe the internal rules should be improved, should be changed, in order to leave less space for manoeuvre, which today is very large.”

MEPs themselves are in charge of their internal rules of procedure.

Kessler's comments came as a consortium of journalists called The MEPs Project published an investigation about the possible misspending of office allowances.