China is considering building a high-speed train line to connect Beijing and the U.S.

The railway, called the "China-Russia-Canada-America" line, would stretch more than 8,000 miles long, according to AOL.

Wang Mengshu, a railway expert from the Chinese Academy of Engineering, said the "bullet trains can run at 350 km per hour, enabling passengers to travel from northeastern China to the US in less than two days."

The train's route would move from northeastern China through eastern Siberia and cross the Bering Strait through an underwater tunnel into Alaska. The tunnel would be 125 miles long, The Washington Post reported.

"Right now we're already in discussions," Mengshu said. "Russia has already been thinking about this for many years."

The railway would be 1,800 miles longer than the Trans-Siberian railroad. The undersea tunnel would be four times the length of the English Channel.

It is not been revealed whether the Chinese government has consulted the U.S., Russia or Canada about the train line, The Guardian reported.

The China-U.S. line is listed in the Beijing Times as one of four international high-speed rail projects that are currently under development. The first line would run from London through Paris, Berlin, Warsaw, Kiev and Moscow. It would split into two routes, with one running through Kazakhstan to China and the other running through eastern Siberia. The second line would start in the western Chinese city of Urumqi and then run through Kazakhstan, Uzbekistan, Turkmenistan, Iran and Turkey to Germany. The third line would start in the southwestern city of Kunming and run to Singapore.

But the cost could present a dilemma that might prevent the railway from being built.

"The ... line could cost north of $200 billion-$52 billion to construct an undersea tunnel to cross the Bering strait and $172 billion for the rest of the railway across land. That would account for well over half of China's already massive high-speed rail budget of $300 billion," Quartz reported