Toyota Motor announced it was joining forces with Chinese battery manufacturers Contemporary Amperex Technology Limited (CATL) and BYD Auto to increase its global sales of electric and plug-in hybrid vehicles.

Toyota said it aimed to switch around 50% of its global sales to electrified powertrain vehicles by 2025, or some 5.5m vehicles based on the company's forecast global production for that year.

This is a full five years ahead of its previous schedule and includes around 1m zero-emission vehicles, including electric and hydrogen fuel cell vehicles, with the remainder made up mainly of plug-in hybrids.

Its new partnerships with CATL and BYD will be essential to secure sufficient lithium-ion battery supplies meet this target.

The decision came as the Japanese government announced stricter average fuel efficiency regulations for the 2030 fiscal year, which analysts said would require automakers to increase the proportion of low- and zero-emission vehicle sales to between 20% and 30% by that year from very limited levels at present.

Governments elsewhere including in Europe and China are also introducing legislation requiring minimum sales quotas for electric and plug-in hybrid vehicles.

Toyota has been developing its own lithium-ion EV battery technology for many years and has a strategic partnership with Panasonic to co-develop and manufacture prismatic batteries in the future.

Last week Toyota also announced a partnership with Subaru to produce a battery-powered SUV on a shared platform.