XI'AN - The nation has the capability to build an expressway linking up Tibet Autonomous Region and Qinghai Province in west China if major technical barriers are overcome, a chief technical consultant for the planned project said on Tuesday.

If China can overcome the technical barriers, an expressway linking Tibet Autonomous Region and Qinghai Province in west China is feasible, a senior consultant with the project said Tuesday.

"Technically, we have the confidence to build the Qinghai-Tibet Expressway," Wang Shuangjie, Party chief of the CCCC First Highway Consultants Co., Ltd., said.

Heading a technical support team for the project, Wang said the primary technical barrier lies in the 500-km frozen earth belt along the planned 1,900-km expressway that links Tibet's regional capital of Lhasa with Qinghai provincial capital Xining.

Lhasa is the only regional capital that's not connected by China's expressway network, but the Sichuan-Tibet highway, along with Qinghai-Tibet highway and Xinjiang-Tibet highway, are the three major roads to Tibet.

Extreme conditions on the Qinghai-Tibet Plateau, such as high altitude, low oxygen content, strong solar radiation and freezing temperature, pose challenge to the expressway's construction and its future maintenance, Wang said.

The expressway will span areas where the average altitude is above 4,500 meters and annual average temperature below zero.

Wang and his team also need to address problems concerning the possible environmental effect of the expressway and come up with proper technology to repair the fragile ecological environment once it is damaged.

He said the suggestion to build the expressway based on the existing roadbed of the Qinghai-Tibet Highway is not feasible due to price.

Currently, China has completed the construction of the roadbed of the expressway's 300-km section between Xining and Caka in Qinghai, while construction of the 400-km section linking Xining with Golmud is still under way.

The rest of the 1,100-km section remains a hard nut to crack for engineers, but what was learned in building the high-altitude Qinghai-Tibet railway may help.

Opened in 2006, the highest railway in the world was lauded as an engineering feat for covering hundred of kilometers over harsh terrain and frozen ground.