The U.S. banking giant Citi sold its 2.71-percent stake in Shanghai Pudong Development Bank (SPDB) for around $668 million.

Citi China CEO Andrew Au said the transaction marks a new phase in its longstanding strategic relationship with SPDB.

"China remains a top priority market for Citi and in 2012 we will continue to invest in China in support of our growing client base across all lines of business," Au added.

Earlier this year, the U.S bank has won approval to set up its own sole-branded credit card business in China after running a business with SPDB for almost a decade.