Contract countdown -- Will UAW strike when GM deal expires?

DETROIT – The United Auto Workers union is letting its contract with General Motors expire at 11:59 p.m., increasing the likelihood of a strike as early as Sunday night.

UPDATE: UAW announces national strike against General Motors

The union told members they should report to their jobs as scheduled Sunday. 

The main negotiation points are wages, health care and job security as GM could potentially idle some manufacturing plants.

Local 4 has confirmed some union chapters are already preparing for a possible strike.

RELATED: 850 UAW Aramark workers in Michigan, Ohio strike

The UAW signed indefinite contract extensions with Fiat Chrysler and Ford, but a protest was held outside Ford's headquarters. Union members, like Eric Truss, have concerns because the negotiations with GM impact the entire Big Three.

Truss said a strike from GM workers would put Ford and Fiat Chrysler on notice. 

Another complication is a federal investigation into current and former UAW officials accused of embezzling thousands of dollars.

"There is a concern about the scandal and who's going to be caught up in it, but right now I think most members are just concentrating on the contract," Truss said.

GM released the following statement Saturday evening:

"We continue to work hard on solutions to some very difficult challenges. We are prepared to negotiate around the clock because there are thousands of GM families and their communities – and many thousands more at our dealerships and suppliers -- counting on us for their livelihood. Our goal remains on building a strong future for our employees and our business."

"While we are fighting for better wages, affordable quality health care and job security, GM refuses to put hard-working Americans ahead of their record profits of $35 billion in North America over the last three years," said UAW Vice President Terry Dittes. "We are united in our efforts to get an agreement our members and their families deserve."

Union officials will hold a press conference Sunday morning to officially announce Saturday's decision.