By Chayut Setboonsarng

PATTAYA, Thailand (Reuters) - Toyota ( TM ) launched a public transport pilot on Thursday with nine fully electric Hilux Revo pickup trucks in Thailand, a key Southeast Asian battleground for electric vehicles where Chinese players are challenging the dominance of Japanese automakers.

"The battery EV Revo have been modified into song-taews for public transportation," Toyota Motor Thailand Executive Vice President Surapoom Udomwong said Thursday, referring to the pickup trucks that have been re-purposed for public transit.

A motorcade of Toyota ( TM ) electric pickup trucks drove through the Thai seaside city of Pattaya some 100 km (62 miles) east of Bangkok, where the vehicles were deployed for fixed-route transit.

The world's top-selling automaker's move in Thailand comes as Chinese EV brands make inroads into the region's main auto assembly and export hub.

Japanese carmakers, such as Toyota Motors, Honda Motors and Isuzu Motors ( ISUZF ) have for decades dominated the Thai auto sector.

But government subsidies and tax incentives have brought a wave of investment from China, with its EV automakers committing more than $1.44 billion worth of investments in Thailand.

Chery Automobile would be the eighth Chinese brand to invest in the country, following BYD, state-owned Changan Automobile and Great Wall Motors, the government said this week.

Toyota ( TM ), which controls about a third of the Thai market, will deliver a dozen electric pickup trucks to Pattaya.

"This is a memorable day," said the city's mayor Poramet Ngampichet. "Pattaya is a major tourist city for Thailand and so lowering pollution is important."

Poramet said he hoped to convert Pattaya's total fleet of 700 song-taews into EVs.

Toyota ( TM ) has previously announced plans to mass produce the battery Hilux pickup truck by 2025, but did not specify where they would be made.

Pickup trucks are popular in Thailand, accounting for about half of vehicle sales.

Isuzu ( ISUZF ) plans set up a plant in Thailand to make the electric version of its D-MAX pickup truck, with plans for domestic sales and exports, according to the Thai government.

(Additional reporting Artorn Pooksasook; Editing by Tomasz Janowski)