Union members of Hyundai Motor Co. and Kia Motors Corp. began to cast their ballots over whether to authorize strikes, union officials said Tuesday, amid little signs of progress in averting potential work stoppages. The result of the vote by some 45,000 unionized workers of Hyundai is scheduled to be released early Wednesday morning, said Kwon Oh-il, a spokesman for the Hyundai union. He said ballot boxes were planned to be transported to Ulsan for vote counting around 10 p.m. Ulsan is home to Hyundai\'s main assembly plants, located some 410 kilometers southeast of Seoul Separately, about 33,000 union workers of Kia were to vote until 8:20 p.m. and the results were expected to be released around midnight, according to a Kia union official. He declined to be identified, though he did not give any reason as to why. Hyundai and Kia are the two major flagship units of Hyundai Motor Group, the world\'s fifth-largest automaking group. Kwon expressed confidence that the union members would overwhelmingly authorize a work stoppage, because the management did not make any meaningful offers. A potential strike requires majority approval from union members. If the strike is authorized, it does not mean that the union can down tools immediately because of a scheduled mediation by a state-run labor body. By law, a union cannot go on strike during mediation by the National Labor Relations Commission, which usually lasts 10 days. The two unions called for the commission\'s intervention to try to work out differences with the managements over a wage deal last week soon after declaring their negotiations with the managements collapsed. The Hyundai union demanded a hike of 130,498 won (US$117) in basic salaries and an extension of the retirement age to 61, as well as a bonus equal to 30 percent of the company\'s net profit. Last year, the carmaker posted a net profit of 9 trillion won ($8 billion). The Hyundai union also said its voice should be heard when the company decides to set up a new overseas assembly plant. Hyundai has assembly plants in China, the United States, India, Turkey, the Czech Republic, Brazil and Russia. Last year, the combined production at Hyundai\'s overseas plants reached 2.5 million vehicles, compared with 1.91 million units at their plants in South Korea. Officials of the two unions and their managements are set to hold their first separate meeting with their counterparts of the commission Wednesday, according to the commission. The mediation is set to end on Aug. 19 when the commission can either ask the unions and the managements to hold more negotiations or halt its mediation, meaning the unions can go on strike, according to the commission. Kwon said union leaders will decide a future course of action on Aug. 19 on the looming strike. He said last week that his union will go on a strike, no matter the outcome on Aug. 19. Strikes have plagued Hyundai Motor for decades. The unionized workers have downed tools every year due to wage disputes since 1986, except in 2007, 2009, 2010 and 2011, according to the carmaker. Kia\'s union went on strike every year, except in 2010 and 2011, since 1999, when the country\'s No. 2 carmaker was taken over by Hyundai following the 1997-98 Asian financial crisis. Three other carmakers in South Korea -- GM Korea Co., the local unit of U.S. automaker General Motors Co.; Renault Samsung Motors Co., the local unit of French automaker Renault SA; and Ssangyong Motor, the local unit of Indian sports utility vehicle maker Mahindra & Mahindra Ltd. -- reached wage deals with their unions in recent weeks. Separately, Hyundai and Kia have performed poorly this year, compared with their global peers. The combined market capitalization of the two carmakers stood at 73.1 trillion won as of Friday, up 2.93 percent from 71.3 trillion won tallied on Jan. 1, according to data compiled by local financial companies. In comparison, Toyota and Honda saw their combined market capitalization jump 40.9 percent to 32.6 trillion yen ($335 billion) during the cited period, the data showed. It also showed that the combined market capitalization of U.S. carmakers, including Ford, surged 24.7 percent to $116.7 billion.