She could face charges for complicity in fraud and misappropriation of public funds for having referred a case involving Tapie and partly state-owned bank Crédit Lyonnais to arbitration over his 1993 sale of sports group Adidas.
An IMF spokesperson repeated the organisation’s support for its executive director.
"The executive board has been briefed on that matter, including recently, and continues to express its confidence in the managing director's ability to effectively carry out her duties," he said.
French Finance Minister Pierre Moscovici has declared that she enjoys “all the confidence of the French authorities” but government spokesperson Najaut Vallaud-Belkacem on Friday said that of Lagarde is charged “they will doubtless ask her to quit her job”.
Tapie on Friday told Europe 1 radio that Lagarde’s judicial fate “doesn’t concern me at all”, insisting that she was his opponent in the affair.
But prosecutors suspect that she was told to go easy on the former Olympique Marseille boss because he supported Nicolas Sarkozy’s 2007 presidential bid.
He would not have been able to pursue his case in the courts because he was bankrupt at the time, they point out.
The arbitration panel awarded him damages that came to 403 million euros when interest was added, allowing him to salvage his finances and career.
Tapie claimed Friday that he ended up with less than 100 million euros, after paying expenses, debts and tax arrears.