Exhibit 10.28.3

January 1, 2012

Dr. Robert L. Joss

Re: Consulting Agreement Renewal

Dear Bob:

This letter sets forth our mutual understanding that the Consulting Agreement
dated April 5, 2010, as amended on October 28, 2010, between you and Citigroup
Inc. (the “Consulting Agreement”) shall continue in effect on the same terms and
conditions from January 1, 2012 through December 31, 2012 with one additional
change. In a modification of paragraph 1 of the Consulting Agreement, you agree
to provide consulting advice to Citi from time to time on projects as agreed by
you and me.

If this arrangement is acceptable to you, please sign and return one copy of
this letter to me.

 

Citigroup Inc.

By:  /s/ Vikram S. Pandit                           By:  /s/ Robert L.
Joss                           Vikram S. Pandit   Dr. Robert L. Joss Chief
Executive Officer

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