General Motors (GM) - Get Report shares traded lower Monday after nearly 50,000 members of the United Auto Workers Union went on strike in a move that could shut down production at the biggest U.S. carmaker for several days.

The nationwide strike action, the first in more than a decade, followed failed talks between GM and UAW officials over a new four-year contract broke down late Sunday, sending 48,000 workers to picket lines at 33 plant and 22 warehouses around the country. Talks are scheduled to resume Monday morning, but the two sides remain far apart on key issues such as profit sharing, healthcare benefits and plant closures under CEO Mary Barra.

"We presented a strong offer that improves wages, benefits and grows U.S. jobs in substantive ways and it is disappointing that the UAW leadership has chosen to strike at midnight tonight," GM said in a statement Sunday. "We have negotiated in good faith and with a sense of urgency. Our goal remains to build a strong future for our employees and our business."

GM shares fell 4.22% to $37.22 in trading Monday, a move that trims the stock's year-to-date gain to 11.3%.

Ted Krumm, who heads the UAW's negotiating team, focused on the issue of plant closures during a question-and-answer session with the media Sunday, an issue that has also raised the ire of President Donald Trump in the past. He also invoked memories of the $50 billion bailout GM received from the federal government at the peak of the global financial crisis in 2009.

"General Motors needs to understand that we stood up for GM when they needed us," Krumm said. "These are profitable times and we deserve a fair contract."

GM posted stronger-than-expected adjusted earnings for its fiscal second quarter, with a bottom line of $1.64 per share that was down 9.4% from the same period last year but firmly ahead of the Street consensus forecast of $1.44 per share. Group revenues, GM said, came in at $36.1 billion, down modestly from last year and largely in-line with analysts' forecasts.

Looking into 2019, GM said it sees full-year earnings in the range of $5.91 to $6.75 per share, with capital expenses in the region of $8 billion to $9 billion. Adjusted earnings, GM said, were held in the range of $6.50 to $7.00 per share.

GM said its North American earnings rose 11.1% to $3 billion, offsetting a slump in international profits linked to a $400 decline in China income. GM delivered 747,000 vehicles in the U.S., the company said, led by record sales for crossover vehicles, which rose 17% from the same period last year.

GM's main U.S. rival, Ford Motor Co. F, has also been slashing jobs and shuttering plants as part of global overhaul it hopes will save it billions over the next few years.

"Ford is a family company and saying goodbye to colleagues is difficult and emotional," CEO Jim Hackett said in a company-wide email earlier this spring. "We have moved away from past practices in some regions where team members who were separated had to leave immediately with their belongings, instead giving people the choice to stay for a few days to wrap up and say goodbye."

Ford is planning to close plants in France and Wales, having already reduced production at facilities in Spain and German and shuttered a plant in Russia, in order to reach the 12,000 jobs cut target, nearly a quarter of its workforce, although the company said many will come from voluntary separation agreements.

Last week, however, Moody's Investors Service lowered its headline rating on Ford to Ba1, one notch below investment grade status, marking the first time Ford's debt has been considered "junk" since it reclaimed a triple-B rating in 2012.

Moody's said Ford's ongoing global restructuring plans will cost around $7 billion in cash -- and $11 billion in overall charges -- that will lead to negative free-cash flow over the next two years amid weakening global auto markets. Ford still holds investment grade ratings from Standard & Poor's and Fitch.