Wal-Mart Stores Inc said on Friday that its U.S. marketing team would now work under the leadership of its chief merchandising officer rather than as a separate group as the world's largest retailer works on improving its communication with shoppers.

Under the new plan, Walmart U.S. Chief Marketing Officer Stephen Quinn will report to Walmart U.S. Chief Merchandising Officer Duncan Mac Naughton. Previously, Quinn reported directly to Bill Simon, the president and chief executive officer of the business.

Mac Naughton, who is responsible for merchandising across Walmart's more than 3,850 U.S. stores, continues to report directly to Simon.

The shift comes as Walmart sees a need for better coordination between the two groups. Shopping and advertising are being quickly transformed by the Internet, social media, smartphones and other shifts in both shoppers' behavior and reaching shoppers with the right campaigns.

Walmart U.S. finally saw sales at existing stores grow during the fiscal third quarter after nine consecutive quarterly declines. Its efforts during the holiday season, such as offering a wider variety of merchandise, a price guarantee and bringing back a broader layaway plan, appeared to be successful, though quarterly results are not due until February 21.

Mac Naughton is familiar with running merchandising and marketing together. Before he joined Walmart in 2009, Mac Naughton was the executive vice president of merchandising and marketing at grocer Supervalu Inc . He has been chief merchandising officer of Walmart US for a year after serving in other merchandising roles.

Quinn, who joined Walmart in 2005 and got his current role in 2007, leads marketing efforts including customer research, strategy, e-commerce marketing, private brands and customer communications.

The announcement came in a memo sent to U.S. employees on Friday that was obtained by Reuters.

Shares of Wal-Mart were down 0.4 percent at $60.75 in afternoon trading, in line with the decline in the broad market.

(Reporting by Jessica Wohl in Chicago; Editing by Lisa Von Ahn and Matthew Lewis)

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