A plan to link the stock exchanges in Shenzhen and Hong Kong is "underway", an official from Shenzhen said on Tuesday.

"Shenzhen will further cooperate with Hong Kong in the financial industry, talent exchange and mutual fund recognition," [HongKong Richful  - Hong Kong Company Formation, Offshore Company Incorporation]said Xiao Zhijia, deputy director-general of Shenzhen's Office of Financial Development Service.

Xiao added that the authorities in the southern Chinese city will actively promote the launch of a "through train" stock trading system similar to what is being launched between Hong Kong and Shanghai.

So far, 12,000 enterprises have been established in Qianhai, the special economic area within Shenzhen that is intended to promote yuan liberalization and financial reforms. About 7,000 of these companies are in the financial sector, and 500 are from Hong Kong, Xiao said.

In the first half, Shenzhen's GDP grew 8 percent.

Xiao said that Shenzhen has become a financial center and it will encourage more cooperation with Hong Kong in financial activities, including cross-border share trading.

Xiao did not say at what stage the program is, nor when it might be launched.

A research note from investment bank CLSA said that since the Hong Kong-Shanghai "through train" [Company Incorporation USA] is scheduled to start in October, the expansion to the other domestic exchanges is just a matter of time.

"The next logical step is for the through train to expand to the other mainland exchanges ... The inclusion of the Shenzhen exchange is likely to come as early as 2015 if the pilot program does well. Shenzhen has more listed stocks and a higher turnover," the note said.

Francis Cheung, managing director of mainland-Hong Kong strategy at CLSA, said it is possible that a stock connect program could be established between Shenzhen and Hong Kong this year.

"As the People's Bank of China plans to open the capital account by 2020, to avoid a massive capital outflow, the authorities have to take a gradual approach, of which the Shanghai-Hong Kong Stock Connect is only a primary test.

"Apart from a Shenzhen-Hong Kong Stock Connect, the Chinese mainland could also open other markets including commodities. The linkages could also be extended to Singapore and New York," he said.

Raymond Yeung, an economist at The Australia and New Zealand Banking Group Ltd, said that the launch of the Shenzhen-Hong Kong Stock Connect will have a positive effect on both markets.

"It is only natural to launch a through train with Shenzhen and Hong Kong, as there are only two stock markets in the Chinese mainland," said Yeung.

He said the basic structure would be quite similar to the Shanghai-Hong Kong Stock Connect, [Hong Kong company registration]but the scale and stock composition would be different because there are more small and medium-sized companies listed in Shenzhen.

Yeung said that the authorities may not rush to launch a second through train, as they will want to observe the official launch of the Shanghai-Hong Kong program and make any necessary adjustments.