Western Digital is considering fresh investment to build another flash memory chip plant in western Japan in an effort to show its commitment to the country, a source familiar with the matter said.

The California-based company is embroiled in a dispute with business partner Toshiba Corp over plans to sell the Japanese firm's prized semiconductor unit and is arguing that it should be given exclusive negotiating rights.

The two firms operate four memory chip plants in Yokkaichi through their joint ventures. Their fifth plant is currently under construction.

The amount of investment and a timeline for the plant's construction have not been decided, the source said, who was not authorized to speak on the matter and declined to be identified.

The source also said Western Digital CEO Stephen Milligan will visit Japan next week for talks with Toshiba to resolve the spat.

A spokesman for Western Digital could not be immediately reached for comment.