Mao's vision of borrowing water from the Yangtze for the north had an almost profound simplicity, but engineers and scientists spent decades debating the project before the government approved it, partly out of desperation, in 2002.
The pair debated the project - initially running from London to Birmingham, and later northwards - which has large support from Labour and the coalition, after a Daily Politics interview with David Tice speaking about the New Economics Foundation report on HS2.
She further explained that it would not be right for her to comment while the State Department was still debating the project.
The cost projections have been one focus of the debate over the project, with critics calling for more financial detail beyond the current estimate of $300 million.
The debate between the project's supporters and its opponents has been polite but passionate.
In between, though, Congress, the courts and the Nuclear Regulatory Commission will all debate whether the project should go forward.
The action followed three years of debate over the project, which had been strongly supported by Gov. James E. McGreevey.
The Institute for Economic Affairs, which has questioned whether HS2 is commercially viable, is to hold a debate on the project that will see its business plan come under forensic scrutiny.
Meanwhile, the Islamic Leadership Council of Metropolitan New York and other groups are holding a meeting in New York this weekend to discuss how to respond to the anti-Islamic sentiment flaring up in the debate over the project.
While not specifically addressing those concerns, Liu said that "security" was central to the debate surrounding the project, adding that the UK has "a state-of-the-art supervision regime and legal system".
