Environmental protection has aroused great concern as the Chinese government faces criticism from overseas media for neglecting the environment as it seeks high-speed economic development, at an eight per cent average annual growth rate.

"It's the first time for the Chinese government to pour such a large amount of money on environmental protection alongside a railway," railway construction director Huang Difu says.

"The railway construction is monitored by a third party as it proceeds as we have introduced an environmental inspector," Huang told the Beijing-based newspaper.

"We have to better carry out environmental protection because we are under observation by a third party inspector," a head of the construction company says. He declined to give his name.

Railway construction deputy director, La Youyu, says "as the railway construction proceeds, we must pay attention to the environment."

"The Tibetan antelopes and the third party inspector are our bosses," some construction workers commented to the newspaper.

The Qingzang railway is the highest railway in the world with an average altitude of more than 4,000 meters.