* January total sales up 4 percent in Mexico
* January same-store sales down 0.6 percent in Central America
MEXICO CITY Feb 6 (Reuters) - Mexico's biggest retailer, Wal-Mart de Mexico, said on Wednesday that sales at its Mexican stores open for at least a year fell 0.3 percent in January from a year earlier.
The Mexican affiliate of Wal-Mart Stores Inc said total sales, including those from newly opened stores, increased 4 percent in January from a year earlier.
Same-store sales in Central America fell 0.6 percent in January from last year.
Wal-Mart de Mexico, known locally as Walmex, opened three new stores and restaurants in January in Mexico and Central America, the company said.
Walmex is under investigation by U.S. and Mexican authorities over allegations that it bribed local officials to speed up store openings.
Mexico's anti-corruption body said late last year that it had so far found no irregularities in its probe of permits and documents given to the retailer to open stores, but two audits are still underway.
The company may still face sizable fines in the United States related to the allegations after a report by the New York Times provided more details about the scope of the alleged misconduct.