TOKYO (Reuters) -- Toyota Motor Corp. plans to start mass producing plug-in hybrid vehicles in 2012, with a projected first-year output of about 20,000 to 30,000 units, the Nikkei business daily reported on Saturday.

Toyota has said it would start leasing 500 plug-in cars globally by the end of this year, primarily for government and corporate use, but has not said when it would commercialize them.

Toyota's plug-in hybrids would fan competition against General Motors' Chevrolet Volt plug-in, which can also be charged at home through an electric socket

GM is aiming to launch the Volt -- a showcase vehicle for its effort to reinvent itself after filing for bankruptcy last month -- by the end of 2010 and plans to have a total 14 hybrid models in production by 2012.

Plug-ins can be cleaner than regular hybrids as they can run purely on electricity, but the need for more batteries makes them expensive.

Toyota wants to price its plug-in hybrids at a comparable price to Mitsubishi Motors Corp.'s all-electric car, which debuts this month to fleet customers in Japan at 4.59 million yen ($47,800) before government subsidies, the Nikkei said, without citing sources.

Toyota's new Prius gasoline-electric hybrid costs less than half that, starting at 2.05 million yen in Japan.

Toyota's plug-ins will be able to run 20-30 km (12.4-18.6 miles) on battery power alone at full charge, the paper said.

Toyota has said the car will be powered by lithium-ion batteries developed and produced by its joint venture with Panasonic EV Energy Co.

A Toyota spokesman said the company could not comment on future product plans.