Citigroup shifted the roles of some of its top executives today, including promoting Americas executive Manuel Medina-Mora to lead the bank's worldwide consumer operations and moving Citi Holdings head Mike Corbat into an international role.

According to a memo from chief executive Vikram Pandit and president John Havens sent, the bank is giving the two executives and top lieutenants more responsibility in a major shakeup of its leadership roles that will take effect the first of the year.