Xing Jun, a team leader of Chongqing Yuhan Lithium Ion Battery Materials Co, a wholly-owned subsidiary of SK Group, also says the key reason for his company investing $100 million in the Sino-Korean Industrial Park is the potentially huge market of the western region.

That belief persuaded him and SK Group heads to persist even in 2012, when the fallout of former city chief Bo Xilai's corruption case was at its worst and unnerved many investors.

"What we care about is not the ups and downs of a single person, but the fundamentals of Chongqing, and the fundamentals of Chongqing remain intact," Xing says.

His company will start production in the first quarter of 2014 producing 2,400 metric tons of battery materials a year. SK Group is also in a joint venture building a chemical plant and semiconductor plant in suburban Chongqing.

According to Chongqing government data, by the end of last year, 107 South Korean enterprises had registered in the municipality with an implemented investment of $316 million. Fortune Global 500 companies such as Hyundai Motor Company and Pohang Iron and Steel Co Ltd are negotiating with the Chongqing government over major deals.

Closer business ties have also resulted in increased demand for travel with the number of direct flights between Chongqing and Seoul increasing from two to four a week.

However, officials of the Liangjiang New Area say attracting foreign investment was not its main focus. They are more concerned with fostering industry conglomeration.