* Next Mazda2/Demio first product under SKYACTIV series

* New Mazda2/Demio to go on sale in Japan in H1 2011

* CEO: not thinking of alliances other than with Ford

* Mazda shares gain 1.4 pct, vs Nikkei’s 1.7 pct drop (Adds CEO comment on alliances, updates share price)

By Chang-Ran Kim, Asia autos correspondent

TOKYO, Oct 20 (Reuters) - Mazda Motor Corp 7261.T said on Wednesday its next Mazda2/Demio subcompact would get fuel economy of 30 km/litre (70 mpg) without the help of an electric motor, likely making it the most fuel-efficient gasoline car on the road.

The vehicle will be launched in Japan in the first half of 2011 as the first product to be equipped with Mazda’s next-generation gasoline and diesel engine and transmission technology, dubbed SKYACTIV.

Mazda is aiming to improve fuel economy on its cars by 30 percent by 2015 compared with 2008 levels by introducing the SKYACTIV technology on all of its cars by around 2016. It plans to build on its current technologies to eventually develop hybrids, plug-in hybrids and pure electric cars beyond 2015.

Japanese minivehicle maker Daihatsu Motor Co 7262.T has also said it aims to develop a gasoline car that achieves fuel economy of 30 km/litre -- equivalent to what the "mild" hybrid version of Honda Motor Co's 7267.T new Fit subcompact gets.

“I promise that we will offer the Demio at a lower price than a hybrid of the same segment,” Chief Executive Officer Takashi Yamanouchi told a news conference, declining to elaborate.

Honda’s Fit hybrid, which went on sale this month in Japan, starts at 1.59 million yen ($19,480).

While Mazda has no hybrid system of its own, it is seen as among the most advanced automakers in internal combustion engine and weight reduction technology.

Mazda said its new direct injection gasoline engine achieves big mileage improvements mainly due to the world’s highest engine compression ratio.

NO ALLIANCE OTHER THAN FORD

Regarding news that Ford Motor Co F.N is planning to sell most of its 11 percent stake in Mazda, worth just over $500 million, Yamanouchi repeated Mazda's official statement that their strategic relationship remained intact.

A source with knowledge of the matter told Reuters at the weekend that top shareholder Ford may sell the stake in Mazda by the end of the year. Ford and Mazda have not confirmed the plan. [ID:nTOE69H02T]

“We have an agreement to continue our strategic partnership with Ford. Therefore, we are not thinking at all of forming an alliance with companies other than Ford,” Yamanouchi said.

“In any case, under any circumstances we believe it is important to maintain the Mazda brand.”

Despite their wide-ranging cooperation, Mazda and Ford have gone their separate ways in developing cleaner vehicles. Mazda in March turned to Toyota Motor Corp 7203.T for help in developing its first hybrid car.

Mazda shares rose 1.4 percent on Wednesday, outperforming a drop in other Japanese auto stocks and the benchmark Nikkei average's .N225 1.7 percent fall. (Editing by Joseph Radford and Chris Gallagher)