Kia Motors to boost U.S. business

SEOUL (Reuters) - South Korea's Kia Motors aims to boost its U.S. production capacity by one fifth next year, to meet soaring demand for new models such as the Optima sedan in the world's second-biggest auto market.

Kia said on Thursday it will invest $100 million to boost capacity.

The annual capacity of Kia's Georgia plant will increase to 360,000 vehicles starting in 2012, from the current 300,000, the carmaker said.

Kia, an affiliate of Hyundai Motor, also said it will start producing the 2012 Optima sedan in September this year at its Georgia plant, which currently produces the Sorento SUV and Hyundai Motor's Santa Fe SUV.

Kia has hired nearly 1,000 workers in preparation for the addition of a third shift - which begins later this month.

Kia saw its U.S. sales jump a whopping 53.4 percent in May to hit an all-time high for third straight month, fueled by a nearly three-fold jump in Optima sales.

Kia and Hyundai, which together rank fifth in global car sales, saw their combined market share top 10 percent for the first time in the United States in May, outperforming the market as their Japanese rivals suffered from sales slump.

"Kia is experiencing unprecedented growth in the U.S," Ahn Byung-mo, group president and CEO of Kia Motors America, said.

(Reporting by Hyunjoo Jin; Editing by Erica Billingham)