Hyundai Mobis Co. ranked seventh in a global car parts makers' sales rankings last year, down one notch from a year earlier, due to lower demand from its captive buyers, an industry association said Tuesday.

The country's biggest auto parts maker by sales took seventh place, with sales of 30.5 trillion won ($27.2 billion) in 2016, the Korea Automobile Manufacturers Association said, citing data from Automotive News in the United States.

Back in 2006 when Automotive News began to announce the rankings, Hyundai Mobis took the 25th spot and its rankings continued to improve to reach eighth place in 2012. It then kept the post of the sixth-largest car parts maker for three years in a row through 2015, KAMA said. 

Hyundai Mobis earns about 70 percent of its sales from deals with Hyundai Motor Co. and Kia Motors Corp. The three companies are key affiliates of Hyundai Motor Group.

The two carmakers suffered sharp declines in sales particularly in China due to local campaigns against Korean products amid diplomatic rows over the deployment of an advanced US anti-missile system in South Korea.

Experts advised auto parts makers, such as Hyundai Mobis and Hyundai Wia, to invest more in research and development activities, while exploring new customers to reduce their heavy reliance on deals with other Hyundai affiliates within the group. (Yonhap)