Deven Sharma, president of the global credit ratings agency Standard & Poor’s, is stepping down from the role next month.

Douglas Peterson, currently COO of Citibank N.A., will take the reins at S&P, effective September 12, according to a statement from S&P’s parent company McGraw-Hill.

Sharma will take on a special assignment working on the S&P’s strategic portfolio review until the end of the year

when he will leave the company to pursue other opportunities.

Investigations by the U.S. Justice Department and the Securities and Exchange Commission into S&P’s ratings of dozens of mortgage securities prior to the financial crisis reportedly had no bearing on Sharma’s departure, and multiple media outlets say Sharma’s decision to step down came long before the agency’s highly publicized downgrade of the U.S. sovereign debt rating.

Sharma joined S&P in 2006 as EVP of investment services and global sales. He was named president in 2007.

Harold McGraw III, chairman, president, and CEO of the McGraw-Hill Companies, credits Sharma with making S&P “a stronger company” whose global analysts are “focused on the quality, independence, and transparency of S&P’s research and analytics.”

The new man at the head of the company, Peterson, served as CEO of Citigroup Japan from 2004 to 2010, prior to his current role as COO of Citibank. From 2001 to 2004, he was Citigroup’s chief auditor.