Nick Roe has been employed by the bank for three years and will shortly begin his new role as head of Global Prime Finance. Previously he worked for Deutsche Bank and led their Global Prime Services.
Since joining Citigroup he has been credited with the success of the European Prime Finance business.
In further changes to senior management successful duo Ali Hackett and Tom Tesauro, who have both headed Global Prime Finance, will leave the company.
Speaking to dealbook in the New York Times, Ms Hackett said: "It's been an arranged marriage but it's been a heck of a ride,"
The memo, printed in the New York Times, reports that Mr Roe will work from London in his new role.
"We are confident Nick's leadership will help us as we continue to strengthen and grow our position and capabilities," said Steve Bowman, head of hedge fund services at Citigroup.