MEXICO CITY — BCW veteran Alberto Diaz, most recently head of the firm’s operation in Mexico, has joined Walmart to lead corporate communications across the retailer’s largest market outside the US.

In the newly created position, Diaz is charged with coordinating internal and external communications, including local journalists and social media.

Diaz will report to corporate affairs director Claudia de la Vega. His role includes collaborating with employee communications head Samantha de la Parra, external communications and brand head Carlos Herrerias and content leader Monica Fernandez.

Diaz joins Walmart after 15 years at BCW (starting at Burson-Marsteller) across Latin America. Most recently, he oversaw BCW Mexico as managing director. Before that, he served as managing director of BCW Chile and led the firm’s regional client relationship program covering eight markets across LatAm.

Walmart Mexico has more than 200,000 employees and 2,580 stores, a number topped only in the US, where the retail giant has 4,750 outlets.