Honda Motor Co. said Thursday it has developed an automobile emission control system that can slash emissions of harmful agents to less than half the target levels set by the government last year.

The new exhaust gas control system also operates with much smaller amounts of precious metals -- such as platinum, rhodium and palladium -- in its catalytic system, the company said.

The new device was jointly developed with Catalytic Solutions Inc. (CSI) of Oxnard, California, it said. Honda has a 10 percent equity stake in CSI.

The control system uses several kinds of metal oxides, leading to a reduction of up to 70 percent in its use of precious metals, the firm said.

The new device will initially be installed on a restyled Honda StepWGN minivan to be introduced in Japan in April, it said, adding that it will be installed in other Honda vehicles later.

CSI developed the new catalytic coating materials, which will minimize emissions of harmful agents such as nitrogen oxide, hydrocarbons and carbon monoxide, Honda said.