Toyota said Thursday global sales of its hybrid vehicles, first introduced 10 years ago, have topped 1 million, a landmark for the Japanese automaker that leads the world in gas-and-electric cars.

Toyota Motor Corp.'s (TM) cumulative sales of hybrid vehicles totaled 1.047 million as of the end of May. Of those, nearly 345,000 hybrids were sold in Japan, while 702,000 were sold abroad, the company said in a statement.

The Prius is the clear leader, with a total of 757,600 units sold since its 1997 introduction in Japan. Toyota began selling the Prius in North America, Europe and other places in 2000. Last year, the model made up more than 40 percent of hybrid sales in the U.S.

Demand for hybrids, which deliver superior mileage by switching between a gasoline engine and electric motor, has soared amid higher oil prices and greater consumer concern about pollution and global warming.

The Prius, which gets 55 miles a gallon on combined city and highway driving conditions, has been enormously popular as a mid-size sedan, which is a best-selling vehicle category.

"Toyota is clearly ahead of the pack in hybrids," said Tsuyoshi Mochimaru, auto analyst with Deutsche Securities in Tokyo.

Although most automakers are working on hybrids, Toyota has the advantage of selling the technology in its products for nearly 10 years, and using feedback from drivers to make improvements, rather than merely information from labs.

Toyota believes hybrid technology is the way of the future. It offers several other hybrid models, including the hybrid Camry and hybrid Lexus models.

"Hybrids will play a key role throughout our lineup," Toyota spokesman Paul Nolasco said. "That means all vehicle categories."

The company recently started domestic sales of its most expensive hybrid, the $124,000 Lexus LS 600h. It will be exported over the summer, Toyota says.

But not all hybrids sell well, and it remains to be seen whether the technology will boost the Lexus brand.

Hybrid sport-utility vehicles, for example, have struggled in sales compared to the Prius, partly because an SUV doesn't have a green image to start with, analysts say.

Sales of Toyota's RX400h hybrid SUV, sold as the Harrier in Japan, has reached 85,000 worldwide since it was introduced in 2005. Another hybrid SUV, the Highlander, or the Kluger in Japan, has sold 67,000 over the same period.

The Prius, by contrast, has sold 478,800 units since the start of 2005.

Earlier this week, Honda Motor Co. (HMC) said it will discontinue the hybrid version of its Accord sedans. Sales of the Accord hybrid, available only in North America, totaled just 439 last month, while Toyota sold 24,000 Prius cars during the same period.

Honda also said it will stop making the slow-selling Insight hybrid, but will continues to sell the hybrid Civic, which has sold more than 153,000 since going on sale in 2001 in Japan, Europe and North America.

Toyota has, however, repeatedly stressed that the hybrid is the single big ecological technology of the future, holding more potential than the diesel or other innovations.

Toyota officials say hybrids will continue to be important, even with the advent of more futuristic technologies like the electric vehicle and fuel-cells that run on hydrogen.

Toyota produces its hybrids in Japan, in China since 2005, and in Kentucky in the U.S. since last year.