Toyota wants worldwide Prius sales of one million a year by 2010.

The petrol and electricity powered vehicles are being made with its Chinese joint venture partner, FAW.

Hybrids use both petrol and electric motors to double their fuel efficiency and halve their emissions.

FAW is China's biggest carmaker, and already works with Toyota to build both sedans and SUVs. The Prius will be made in Changchun, north-eastern China

The model will sell for between 288,000 and 302,000 yuan ($35,000-$37,000; �20,000-�21,000).

Emission regulations

China is the world's fastest growing car market, but also has five of the ten most polluted cities in the world.

Toyota vice-president Yoshimi Inaba said hybrid cars like the Prius could help China deal with its environmental and energy shortage problems.

"In addition to China's new automobile policy that encourages the use of hybrid vehicles, the introduction of emission regulations on par with those in Europe and the United States is also moving forward."

Earlier this year Volkswagen and General Motors announced plans to explore building hybrid vehicles with Chinese partner companies.