Dominique Strauss-Kahn, the former head of the International Monetary Fund and French presidential aspirant, will face trial on pimping charges after French investigators decided he was connected with a prostitution ring at a hotel in the northern city of Lille.

Strauss-Kahn has admitted attending sex parties at the hotel but has claimed that he did not know some of the women were prostitutes.

The case, which has been ongoing since 2012, is the latest in a number of charges relating to Strauss-Kahn’s personal life and the most recent since he was forced to stand down as the leader of the IMF in 2011, after he was accused of raping a hotel maid in New York.

The decision to charge him with pimping came as a surprise after a public prosecutor had recommended in June that the inquiry be dropped without trial.

"We're not in the realm of the law, we're in ideology. We're sending someone to court for nothing," said Henri Leclerc, one of Strauss-Kahn's lawyers.