(Bloomberg) -- Mexican financial authorities are close to approving an offer by billionaire Fernando Chico Pardo to buy a 25% stake in Citigroup Inc.’s Mexican retail-banking unit, Banamex, paving the way to list the business as soon as next year. The approval process for Chico Pardo’s stake and his strategic plan for Banamex is in its final stages, according to people familiar with the matter who requested anonymity because because the process isn’t yet final. When Citigroup agreed to the 42 billion-peso ( ...