The long-term development of rail services could see the MTR Corporation realise its goal of transporting passengers between northern Shenzhen and the south of Hong Kong Island within the next decade, the company's chairman said yesterday. Raymond Chien Kuo-fung added that it would not be surprising to see 500km of new metro lines built in mainland cities over the coming 10 years. Dr Chien was speaking in Shenzhen at the inauguration of an investment alliance between Shenzhen and Hong Kong private enterprises. The MTR Corp has been aggressive in its mainland metro investments over the years, with Shenzhen and Beijing being the primary beneficiaries, along with Shanghai. Hangzhou , Tianjin and other key cities are also keen to increase their development of underground railways and have courted the MTR Corp. 'Many government officials from other provinces have visited Hong Kong and discussed possible partnership opportunities with us,' Dr Chien said. 'They are not yet familiar with our rail-plus-property business model, which pays for itself ... The central government has sent people to study our business model and they find it quite attractive. Otherwise, you need to provide long-term subsidies.' In Hong Kong, the MTR Corp develops residential and commercial property along its rail links and uses profits from these developments to subsidise its rail operations. Dr Chien is eager to export this business model to the mainland, which is showing interest in having the company involved in developing key rail infrastructure. The MTR Corp's mainland push, and that of other local firms, was reflected in the launch yesterday of the Shenzhen and Hong Kong Investment Alliance, which seeks to foster greater economic and investment ties between the two cities. Dr Chien said he hoped the success of the alliance would prompt similar tie-ups with other mainland provinces and overseas markets and attract more investments to Hong Kong and Shenzhen.