Kia Corp. posted record monthly sales in the United States in August, while Hyundai Motor Co. reported a decline in numbers, the Hyundai Motor Group affiliates said Wednesday. Kia America sold 83,793 vehicles last month, up 1 percent from a year earlier and marking its highest-ever monthly sales. Cumulative sales in the first eight months of the year rose 3 percent on-year to 590,377 units, also setting a record for the January-August period. The Sportage SUV was Kia's bestselling model, with 18,723 units sold. Hyundai Motor America, on the other hand, saw its U.S. sales decline 2 percent on-year to 86,977 units in August, despite continued strength in hybrid vehicles. Hyundai's hybrid sales jumped 33 percent from a year earlier, setting a record for the month of August. Among major models, sales of the Palisade SUV fell 18 percent on-year to 12,729 units, while the Ioniq electric vehicle lineup also posted weaker sales. In contrast, sales of the Tucson and Santa Fe SUVs increased 18 percent and 5 percent on-year over the period, respectively.