Dominique Strauss-Kahn has resigned from his post as head of the IMF

The head of the International Monetary Fund, Dominique Strauss-Kahn, resigned from his post late Wednesday from a jail cell in New York, where he is facing sexual assault charges.

In a letter made public by the IMF, Strauss-Kahn wrote of the reasons he was standing down with "infinite sadness," but he also forcefully maintained his innocence, according to Los Angeles Times.

"I want to devote all my strength, all my time, and all my energy to proving my innocence," Strauss-Kahn said in a statement released by the Washington-based IMF four days after his arrest on sexual-assault charges. The fund said it will comment "in the near future" on the succession. Strauss-Kahn, 62, had been leading polls for France's 2012 presidential election.

European officials, who have picked IMF heads for 65 years under a deal that also gives the U.S. the lock on the top World Bank post, moved to retain the privilege, with Sweden backing French Finance Minister Christine Lagarde. Russia and South Africa have called for an emerging-market candidate, while some Asian policy makers suggested someone from their region, BusinessWeek reports.