The unionized workers are calling for a 154,833 won ($136) hike in their basic monthly pay along with a 30-percent increase in bonuses and other benefits, the sources said.

The management, however, is opposed to the proposal, citing that the sales have been hurt by Seoul's decision to deploy the Terminal High Altitude Area Defense (THAAD) system on its soil that angered Chinese consumers. China is the company's is the largest export market for Hyundai and its sister company, Kia Motors.

China has opposed the THAAD installation in South Korea as it claimed the battery system's powerful X-band radar system could spy on its military. Seoul in the past has maintained the anti-missile system is aimed at countering missile threats from North Korea.

Workers and management at GM Korea, the local unit of US carmaker General Motors Co., have also held ninth rounds of wage-hike talks as of Thursday without making meaningful headway.

The union asks for a 154,833 won hike in their basic monthly pay along with a five-fold raise in bonuses workers receive, which was not welcomed by the management.

The company has logged weak business performance in recent year, registering over 500 billion won in net losses last year.

Ssangyong Motor, the local unit of Indian automaker Mahindra & Mahindra Ltd., also has held five rounds of talks since June 8, they said.

Representative of the labor union have asked the company to raise the base salary by 118,000 won while the management is being cautious, citing the overall management crisis despite improved earnings.

The labor union of Kia Motor has also demanded the basic salary to be increase and a 30-percent rise in bonus, a level similar made by Hyundai Motor's union.

Renault Samsung Motors, the South Korean unit of French carmaker Renault S.A. meanwhile, will kick off the official wage-deal talks starting this week. (Yonhap)