Premier Li's offer took Downing Street by surprise and British officials insisted that the main rail line will be funded entirely by the taxpayer. But officials held open the prospect of Chinese companies bidding for the concession to run the line once it was built and said they would welcome direct investment in stations and other ancillary projects around HS2.
Ministers are promoting HS2 as a project that can establish the UK as a world-leader in high-speed rail engineering and so are sensitive to the fact that Beijing's offers to finance infrastructure in other countries have often been contingent on awarding building contracts to Chinese companies.
In a letter to the leader of Birmingham city council last month, China Railway Group offered to build connections from the proposed HS2 interchange on Birmingham's eastern outskirts to the airport and cities such as Coventry and Peterborough.
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China Railway Group is a Hong Kong-listed subsidiary of the state-owned China Railway Engineering Corporation and has been instrumental in leading the modernization of the country's domestic rail network.
An official in China Railway Group's international department confirmed the company's interest in the project, which has been valued at £240 million by its other backers.