After rejecting a proposal by General Motors (GM) - Get Report worth more than $7 billion, the United Auto Workers union saw tens of thousands of its GM autoworkers go on strike at 11:59 p.m. ET on Sunday -- the first such major industry walkout in nearly 12 years.

UAW did not respond to specific questions from TheStreet earlier Sunday about the negotiations with the auto giant, but issued a public statement in the morning that the talks failed to resolved long-standing disagreements. It also confirmed that 46,000 hourly union workers would be going on strike at midnight.

A spokesperson for GM, when asked if there were any updates prior to the deadline, said there was "nothing new" as of about 11:30 p.m. ET.

The strike came 24 hours after negotiations failed by midnight Saturday to produce a new contract. 

"Local Union leaders from across the nation met Sunday morning after the 2015 General Motors collective bargaining agreement expired Saturday night and opted to strike at midnight on Sunday," said the UAW in a press statement earlier on Sunday.

"We stood up for General Motors when they needed us most. Now we are standing together in unity and solidarity for our members, their families and the communities where we work and live," UAW Vice President Terry Dittes said in the statement.

General Motors, however, said it made a "strong offer" to union workers that would increase wages, benefits and create more U.S. jobs. It characterized the offer as an over $7 billion investment that included more than 5,400 jobs, higher pay, and improved benefits.

GM called the union's rejection of its offer and planned strike "disappointing."

The automaker put forth a detailed explanation of its proposed offerings that include what GM called "best-in-class wages and benefits" such as wage increases, an "improved" profit sharing formula, ratification payment of $8,000, and new health coverage for autism therapy care, chiropractic care and allergy testing.

It also promised investments in eight facilities in four states, the opportunity to become the first union-represented battery cell manufacturing site in the U.S. and additional new vehicle and propulsion programs.

The 46,000 unionized General Motors workers would join 850 UAW-covered maintenance and janatorial employees who began striking at midnight Saturday at several GM plants in Michigan and Ohio, but who work for Aramark (ARMK) - Get Report .

GM spokesman David Barnas told TheStreet earlier that "we have contingency plans in place to cover any potential disruptions" caused by the strike by Aramark workers.

The walkout of GM's autoworkers could hit the automaker hard, costing the company over a million dollars an hour at each plant that is idled, according to the Ann Arbor-based Center for Automotive Research. Workers would get just $250 a week in strike pay, if they show up to picket. The UAW strike fund totaled more than $721 million at the end of 2018.