The head of the US auto workers union reported "serious movement" on Friday in negotiations to end a strike with automakers Stellantis and General Motors, but saw no progress with Ford.
Nearly 34,000 United Auto Workers (UAW) members are now on strike, a number that has grown since the initial September 15 move to shut down one plant at each of the "Big Three" US car makers.
"I'm happy to report that in the past 24 hours, we've seen serious movement from both (Chrysler owner) Stellantis and GM," said UAW President Shawn Fain in an online video address.
Meanwhile, Ford continues "to pretend they can't afford what we're asking for," he added.
The UAW has previously expanded its strike and recently said the labor action had entered a new stage involving last-minute walkouts.
But on Friday, it did not add any new sites to those already shut down.
Fain said that each of the members of the "Big Three" had now agreed in principle to a 23 percent average wage increase over the four-year life of the agreement under negotiation.
"The companies keep saying they hit their limit and then their limit goes up. We think there's more ground to gain," he added.
The industrial action marks the first joint strike at the three major automakers, as workers push for higher wages and other improvements.
In particular, these relate to the transition to making electric vehicles.
The positive signals follow recent tensions with the UAW announcing last week an immediate walkout at Ford's Kentucky Truck Plant in Louisville, where some of the company's most profitable models are built.
On Monday, Ford appealed to workers to band together against competitors like Japanese carmakers Toyota and Honda, as well as Chinese automakers -- in asking for an end to the strike.