Toyota Motor Corp. is moving to expand its renowned hybrid franchise by developing an all-new hybrid-only model that will be smaller and more affordable than its wildly popular Prius.

The Japanese automaker will unveil a concept version of the car on Jan. 11, the first day of the North American International Auto Show's press preview.

Toyota officials declined to discuss the vehicle, but people familiar with the project say the car, a subcompact, is scheduled to go into production in Japan in late 2011 and roll into U.S. dealer showrooms in early 2012.