UPDATE 1-Exit of SocGen's deputy CEO followed negotiations with U.S. over Libor case -source

Libor case -source@ (Updates with details)

PARIS, March 15 (Reuters) - The sudden departure of Societe Generale's deputy chief executive Didier Valet was agreed as part of negotiations with U.S. authorities on a financial settlement over alleged Libor rigging, a source close to the bank told Reuters.

Late on Wednesday, SocGen announced that Valet was leaving the French bank "following a divergence of approaches regarding management of a specific legal matter".

SocGen did not give any more details in its statement about the legal matter and said Valet had resigned in order to preserve the bank's "general interests".

The source said SocGen believes it has sufficient provisions to cover the settlement and the resignation of the head of SocGen's corporate and investment banking business - Valet - would help reach an agreement with U.S. authorities.

"We believe that on the basis of the negotiations the bank's provisions for a settlement are absolutely adequate," the source said. SocGen's provisions for litigation issues totalled 2.3 billion euros at end-2017.

Valet and SocGen declined to comment and a spokeswoman for the U.S. Justice Department had no immediate comment.

Societe Generale said in its annual report published last week that it was in discussions with the U.S. Department of Justice and the U.S. Commodity Futures Trading Commission in order to reach an agreement to resolve investigations regarding submissions to the British Bankers Association for setting certain London Interbank Offered Rates (Libor).

Last August U.S. authorities charged two SocGen senior treasury executives with taking part in a scheme to manipulate the global U.S. dollar Libor benchmark interest rate.

Valet, who started his career at SocGen in 2000, was chief financial officer of the bank at the time the allegedly inaccurate Libor contributions were made between May 2010 and October 2011.

According to the indictment, the false reports at times led to lower U.S. dollar Libor rates, affecting millions of transactions tied to the benchmark and causing over $170 million in harm to global financial markets, prosecutors said last August.

(Additional reporting by Karen Freifeld in Washington, writing by Maya Nikolaeva; editing by Silvia Aloisi and Susan Fenton)