South Korea's Hyundai Motor Group topped global rivals in terms of vehicles produced in its home country last year, with nearly 45 percent of all cars produced locally, a carmakers' business lobby said Sunday.

The combined ratio of domestic output at Hyundai Motor Co. and its sister company Kia Motors Corp. marked the highest of 44.8 percent among the world's top five carmakers by sales, according to data from the Korea Automobile Manufacturers Association. 

Hyundai Motor and its 34 percent-owned affiliate Kia Motors together form the world's fifth-biggest carmaker by sales.

Toyota Motor Corp. ranked second with a domestic output ratio of 39.2 percent, followed by Volkswagen AG with a ratio of 27.3 percent, General Motors Co. with 22.1 percent and the Renault-Nissan alliance with 19.0 percent, the data showed.

In the past decade, Hyundai and Kia have increased their production at their overseas plants, mainly in the United States, China and Europe to avoid any major production losses due to strikes and sidestep import duties.

"If unionized workers at the country's two major carmakers cause production losses by staging a strike, the companies will have no choice but to produce more vehicles in their overseas plants," an industry official said. "As the automobile industry hires a lot of workers and contributes much to the national economy, the government needs to consider measures to maintain a certain level of production volume at home."

Hyundai Motor has faced a labor strike nearly every year since its militant union was formed in 1987. The only exceptions were in 1994, 2009, 2010 and 2011. (Yonhap)