Subaru Corp. placed a sudden stop on production of its popular Forester and Crosstrek models after discovering a potential steering defect.

The Japanese automaker a week ago temporarily stopped production of the models, its second- and third-most popular cars in the U.S., due to issues stemming from a defect in the power steering mechanisms on both cars, according to media reports.

Production at the company's single plant in Japan shut down a week ago, according to Reuters.

Subaru won't resume production until Monday at the earliest, Subaru spokesman Dominick Infante told USA TODAY in an email.

The defect may affect about 10,000 vehicles in the U.S., "but that number may be smaller" and the vehicles haven't been sold to customers, Infante told USA TODAY.

"The power steering unit issue was discovered very early, and countermeasures are being put in place," Infante said. "Subaru Corporation can confirm that no vehicles with the affected power steering units will be sold to US customers until the vehicles have been repaired."

The issue has not yet affected Subaru's U.S. plant in Indiana.

It's unclear whether the disruption could affect Subaru's sales. The brand has been extremely popular in the U.S., recording an 11th straight year of growth in 2018 and 85 straight months of year-over-year sales increases, according to the company.