Citigroup Inc. C continues to struggle with fixing its regulatory problems. United States Senator, Elizabeth Warren, urged the Office of the Comptroller of the Currency (“OCC”) to impose growth limitations on the company.

In a letter to Acting Comptroller Michael Hsu, Democratic Sen. Elizabeth Warren urged the regulator to curtail the megabank's growth in response to its failure to improve its risk management programs.

Massachusetts Sen. Elizabeth Warren is warning regulators that Citigroup (C) has become “too big to manage” and that federal regulators should enforce stricter restrictions on the bank.

In a letter to Acting Comptroller of the Currency Michael Hsu, Warren contended that Citi's ( C) struggles to fix a string of regulatory issues focusing on data, controls and other problems demonstrate that the bank has become "too big to manage." Reuters had reported on the letter earlier on Thursday.

A prominent Democratic U.S. senator called on a top regulator on Wednesday to impose growth restrictions on Citigroup as the Wall Street bank struggles to fix ongoing regulatory problems. In a letter to Acting Comptroller of the Currency Michael Hsu,

The Massachusetts Democrat called on a top government regulator to restrict the growth of the nation’s fourth-largest bank.