According to Yonhap, the labor union at GM Korea Co., the South Korean unit of General Motors Co., said it is extending its partial strike this week as wage negotiations remain deadlocked. Unionized workers staged a four-hour walkout across all shifts from Tuesday to Wednesday after a two-day partial strike last week. The union is seeking a 149,600-won increase in monthly base pay, 30 million won in performance-based pay for each worker and the assignment of new vehicle production to the company’s domestic plants. A union spokesperson said the workers will strike if there is no progress in wage talks on Wednesday. GM Korea exports about 410,000 vehicles a year from its South Korean plants, with about 85% shipped to the United States, while its overall vehicle sales rose 10.5% from a year earlier to 275,523 units in the January-June period.