Toyota Motor Corp., the biggest seller of hybrid vehicles, wants to boost supplies of its four-model Prius line as demand for the fuel-saving cars is outpacing the company's initial U.S. target of more than 220,000 this year.

"We're tracking well ahead of that," Bob Carter, Toyota's group vice president of U.S. sales, said in an interview this week in Los Angeles. "I've ordered additional production. I'm confident we'll get additional production, but globally we're seeing high demand, particularly in Japan."

Sales of the Prius, including the main liftback model and new v wagon, c subcompact and plug-in version, through April jumped 56 percent from a year ago to 86,027 units. Were that rate to continue, annual deliveries would top 250,000 units, based on a Bloomberg calculation.