Detroit ? United Auto Workers set a deadline of this morning to strike General Motors Corp. if a new contract isn’t reached, even as the two sides continued bargaining late Sunday night, according to a local union Web site.

The deadline to reach an agreement was set for 10 a.m. CDT today, according to a posting on the Web site of UAW Local 160 in Warren.

GM spokesman Dan Flores said the automaker is working with the union to resolve issues. Talks were continuing as of 11:30 p.m. CDT Sunday, Flores said.

“The contract talks involve complex, difficult issues that affect the job security of our U.S. work force and the long term viability of the company,” Flores said. “We are fully committed to working with the UAW to develop solutions together to address the competitive challenges facing General Motors. We will continue focusing our efforts on reaching an agreement as soon as possible.”

UAW President Ron Gettelfinger said as recently as Friday that the union was trying to speed up negotiations and reach an agreement without a strike. The union may be trying to ratchet up the pressure on GM to get a deal done.

The UAW’s contract with GM was set to expire Sept. 14, but the union has been extending it on an hour-by-hour basis since then.