Just a few months ago Toyota was struggling to keep up with demand for its Prius hybrid in North America due to skyrocketing fuel prices. Waiting lists at some dealerships were stretching as long as eight months. But now Toyota may be rethinking its plan to supply more of the hybrids with U.S. production as overall sales volumes sink.

Flagging demand for Toyota's SUV and pickup models led the company to respond to changes in consumer demand by adjusting the production mix at three of its plants in North America. The Prius hybrid had been planned to be built at a plant in Blue Springs, Mississippi, beginning in late 2010. Now production could be pushed back as far as 2011, reports Automotive News Europe, though the company stresses that nothing has been decided yet, and the 2010 plan still stands for the present.

The Prius is already manufactured in Japan and China but the North American market remains the car’s biggest, with more than 130,000 units sold last year alone. The Highlander mid-size SUV, originally scheduled to be built in Mississippi, will still likely be manufactured in Princeton, Indiana, beginning in the first half of next year.

Production of the Tundra full-size pick-up truck, currently built in Indiana and Texas, will be consolidated at the San Antonio plant in the second half of next year. Toyota already temporarily suspended Tundra and Sequoia production in August due to the declining overall market for full size trucks and SUVs.

Supply of Toyota’s hybrid models have also been delayed recently due to a lack of batteries. The carmaker has confirmed that it will build two additional battery plants in Japan to increase the supply of nickel-metal hydride batteries for its hybrid vehicles.