Carlos Tavares, who had been under fire and was expected to leave at the end of his contract, resigned abruptly on Sunday.

The chief executive of the automaker Stellantis, Carlos Tavares, has resigned, the company said on Sunday, amid a decline in profits and slumping sales in its key North America region. Mr. Tavares, 66,

The global automaker’s sales in North America declined over the past year because of high-cost models that dealers struggled to sell.