Grocery workers represented by the United Food and Commercial Workers Local Union 455 in Houston terminated a contract extension with Kroger Co. (KR).

In Houston, where 12,700 workers are involved in negotiations with the Cincinnati-based grocery chain, UFCW members already voted to authorize a strike last month.

Houston workers have been joined by UFCW Dallas Local 540, which also voted to authorize a strike against Kroger.

Dallas Local 540 isn't operating under any contract extension, and Local 408 in Houston has already terminated its contract extension with Kroger.