A special French court will decide today whether to investigate new IMF chief Christine Lagarde's possible role in securing a 285-million-euro (US$406 million) arbitration deal for a controversial businessman.

Lagarde took the helm of the International Monetary Fund this week after her French predecessor, Dominique Strauss-Kahn, quit to faces charges he tried to rape a New York hotel maid.

A French prosecutor has been seeking an investigation into Lagarde's role, saying he had reason to suspect she overstepped her authority in the deal.

A commission at the Court of Justice of the Republic convenes today to decide whether to approve an investigation. The court - a special body that handles cases involving government ministers - can also decide to ask for further information, or decide not to investigate at all.

Lagarde said on France-24 television this week that whether or not the French court decides to investigate, "I have the exact same confidence, and same sense of calm."

The IMF management was aware of the possible investigation when it chose Lagarde as its new chief last month.

Any investigation, if launched, would take months if not years, and might not necessarily result in a trial.