UPDATE 1-Wal-Mart and Washington D.C. in minimum wage showdown
September 05, 2013 at 15:46 PM EDT
WASHINGTON, Sept 5 (Reuters) - District of Columbia Mayor Vincent Gray could decide as early as this week whether to sign a minimum wage bill that could discourage Wal-Mart Stores Inc , the world's biggest retailer, from opening stores in the U.S. capital.