With plant closures looming, GM, Fiat Chrysler warn workers auto industry facing tough future

"In a transforming industry, if we want our company to grow -- and grow jobs -- we can't keep doing things the same way," she said.

GM has drawn the wrath of the UAW and President Donald Trump over plans to halt production at four US plants including a major one in Lordstown, Ohio, a state that could be key to Trump’s re-election bid in 2020.

GM is attempting to sell that plant to a startup company proposing to build electric trucks.

"I have made it clear publicly and in many conversations with elected officials -- including President Trump -- that we are committed to investing in and growing jobs in the US," Barra said.

But she cautioned that, in addition to challenges of changing technology, "we continue to operate in a very uncertain trade environment in a long-lead industry."

After launching contract negotiations with Ford on Monday, UAW president Gary Jones opened talks Tuesday with GM and Fiat Chrysler Automobiles (FCA).

Mark Stewart, FCA's chief operating officer in North America, had a similar message for workers about the need for the industry to prepare for a future that will be dominated by electric and self-driving vehicles.

"Our operational flexibility, the flexibility of our competitive cost structure we created together, are needed to continue to fund these investments with electrification and the future of all of our company," Stewart told labor leaders, according to media reports.

Jones repeated the message he delivered to Ford, saying the union expects to make economic gains and share in profits in the contracts it will sign this coming fall.

"When you needed us, we were there, and we expect no less in return," he noted.