As tighter environmental regulations push demand for zero-emission vehicles, Honda Motor Co. is planning to develop an electric car to debut in the United States by around 2015.

A spokesperson for the company, Japan’s No. 2 automaker, said it was developing an electric car but had not decided when to launch it.

The company also declined to comment on the Nikkei business daily’s report, without sources, that a prototype of the car would be unveiled at the Tokyo Motor Show in October.

The vehicle is expected to be around the size of a minicar, the Nikkei said Saturday.

Other automakers such as Toyota Motor Corp. and Volkswagen AG have also announced plans to launch electric cars in the next few years.

But they say it could take decades for the vehicles to spread due to their high cost, limited driving range and long charging times with the current battery technology.

Nissan Motor Co., Japan’s third biggest automaker, unveiled its electric car Leaf earlier this month with plans to begin selling it in the United States, Japan and Europe toward the end of 2010.