PARIS (AFP) - Corruption investigators in France have seized the assets of French tycoon Bernard Tapie, suspected of having committed fraud as part of an organised gang, judicial sources said on Wednesday.

The charge relates to a 400 million euro (S$653 million) state payout Tapie received in 2008 when Christine Lagarde, now the head of the International Monetary Fund, was France's finance minister.

Lagarde was in charge of the arbitration process that led to the payout and investigators suspect Tapie received preferential treatment in return for his high-profile support for her boss, former President Nicolas Sarkozy.

The French daily Le Monde reported that investigating magistrates had concluded that Tapie "appears to be one of the organisers of a swindle".

The court ordered the seizure of Tapie's assets on June 28, Le Monde said.

The payout to Tapie, now 70, related to a dispute between the businessman and partly state-owned bank Credit Lyonnais over his 1993 sale of sportswear group adidas.

Tapie claimed that Credit Lyonnais had defrauded him by intentionally undervaluing adidas at the time of the sale and that the state, as the bank's principal shareholder, should compensate him.