Mitsubishi Motors president Osamu Masuko said the carmaker has abandoned plans to expand its business tie-up with Proton.

Masuko said it would be difficult for the two companies to embark on major new projects although they will continue existing joint operations, including the licensed production by Proton of passenger cars developed by Mitsubishi.

The Japanese company has been negotiating with Proton since September last year on the Japanese firm's outsourcing of production, joint engine output and its provision of technology for electric vehicles.