Slideshow ( 2 images )

SEOUL (Reuters) - South Korea's Hyundai Motor 005380.KS said it is considering building a car plant in Southeast Asia with Indonesia and Vietnam possible locations - part of efforts to diversify after a sales slump in China.

The automaker does not have a car manufacturing factory in Southeast Asia, although it has some pure assembly operations in Indonesia and Vietnam where cars are made from “knock-down” kits comprised of major component groups.

A diplomatic row between Beijing and Seoul last year over the South Korea’s planned deployment of U.S. anti-missile defense system THAAD has hurt Hyundai and other South Korean firms that are highly reliant on the Chinese market.

Hyundai expects its China sales to reach about 900,000 vehicles in 2018, a recovery from levels last year, vice chairman and heir apparent Chung Eui-sun also said on the sidelines of the consumer electronics show in Las Vegas, according to a company spokeswoman.

Hyundai has not disclosed estimates for 2017 China sales but sales of 900,000 would still be far below its production capacity of 1.65 million vehicles in its biggest market. Chung added that Hyundai is planning to enter China’s fuel cell electric car market, after the automaker unveiled its new fuel cell electric vehicle, NEXO, with an estimated driving range of 370 miles, at the show.