Jeoffrey Guillemard/Bloomberg Citigroup Inc. agreed to sell a 25% stake in its Mexican retail banking unit Banamex to local businessman Fernando Chico Pardo as part of a plan to list the asset publicly.Chico Pardo — via a company owned by the executive and his family — will acquire the stake for about $2.3 billion, Citigroup said in a statement. When the deal closes, as expected in the second half of next year, Chico Pardo will become chair of Grupo Financiero Banamex, according to the statement. New Yor ...