The UK is considering giving China’s state-owned railway builder a role in constructing the HS2 rail line.
Government officials said “preliminary discussions” had taken place, but no “concrete commitments” had been made.
The Chinese railway firm said it could build the line in five years and at a much lower cost, according to a letter seen by Building magazine.
Earlier this week, Prime Minister Boris Johnson divided opinion by approving the scheme.
The decision came despite an official review that said costs could reach over £100bn – well over the £62bn budget.
However, the China Railway Construction Corporation (CRCC) has written a letter to HS2’s chief executive claiming they could complete the line for much less.
It also said it could do it by 2025 rather than the current 2035 target.
According to the Financial Times, who have also seen the letter from the CRCC, the firm said: “We are certain that we can offer a cost that is significantly lower than the projections we have seen.
“The advantages are too great, in our opinion, too great to dismiss on the basis that there are obstacles to overcome.
“You will find that the Chinese way is to seek solutions, not linger on obstacles and difficulties.”
CRCC built most of China’s 15,500-mile high-speed network.
There are questions whether the company could operate to the same level in the UK with the democracy and property rights, protected landscapes, lobbying groups and other obstacles it may face
A Department for Transport official said: “The DfT is always keen to learn from the experience of others and to consider approaches that offer value for money to the taxpayer.”