The worst US auto market since the early 1990s may force Toyota Motor Corp to do something that was once unthinkable: cut its North American payroll.

Asia's largest automaker, which hasn't shed workers in 24 years of building cars in the US, is exhausting options to trim costs after halting work on a Prius plant in Mississippi, idling a Texas truck factory for 15 weeks and planning to pare US and Canadian output next month.

"If we don't see a rebound by the second half of next year, they'll probably have to consider layoffs," said Haig Stoddard, an analyst at forecaster IHS Global Insight Inc in Troy, Michigan. "Toyota was expanding to catch up with demand. Now it's got itself stuck with overcapacity for the first time."