With the partnership announced Tuesday by Honda Motor Co. and General Motors Co., major global automakers have now divided into three competing groups in the development of fuel-cell technologies, with each including a Japanese player.

Key to taking the lead in the market for next-generation environmentally friendly vehicles will be how fast they can come up with ways to reduce exorbitant prices to reasonable levels through cost cuts and economies of scale.

Unlike gasoline-powered vehicles, fuel-cell cars, powered by electricity generated through the reaction of hydrogen and oxygen, do not emit carbon gases when running.