The companies will start by building a new plant in Japan, targeting a production capacity of at least 20 gigawatt hours (GWh), the Nikkei added, without citing sources.

A joint-venture, which the companies unveiled in January, will play a central role in the development of batteries and materials as well as capital investment, the Nikkei said.

Japan's Ministry of Economy, Trade and Industry would provide a subsidy of about 150 billion yen, the newspaper added, without specifying whether that would be only for building the factory.

A Honda spokesperson told Reuters the report was not something it had announced, and there was nothing it could answer about it at this point, while a ministry official said the same. GS Yuasa could not be immediately reached outside of regular office hours.

($1 = 133.9700 yen)

(Reporting by Daniel Leussink, Maki Shiraki and Elaine Lies; Editing by Kirsten Donovan)