WASHINGTON (AP) — Mayor Vincent Gray vetoed a bill Thursday that would force Wal-Mart and other large retailers to pay their employees at least $12.50 an hour, calling it a “job killer” that would not advance the goal of a living wage for District of Columbia workers.

The bill put Washington at the center of a national debate on how far cities should go in trying to raise pay for low-wage workers — and whether larger companies should be required to pay more. Supporters — including unions, clergy and other labor advocates — said Wal-Mart could afford the higher wages, while opponents said the bill unfairly singled out certain businesses and would have a chilling effect on economic development.