BEIJING- China has reportedly commissioned a "preliminary research study" to construct an international rail link connecting its province Xinjiang’s border to Pakistan .

China has allocated funds for preliminary research on building an international railway connecting Kashgar in Xinjiang with Pakistan 's deep-sea Gwadar Port on the Arabian Sea.

"The 1,800-km China-Pakistan railway is planned to also pass through Islamabad and Karachi," Zhang said at the two-day International Seminar on the Silk Road Economic Belt.

"Although the cost of constructing the railway is expected to be high due to the hostile environment and complicated geographic conditions, the study of the project has already started," Zhang added whilst referring to recurring attacks carried out by extremist groups in Pakistan .

Xinjiang itself is in a restive state due to attacks by East Turkestan Islamic Movement (ETIM) militants within the province as well as in Beijing and other Chinese cities.

China and Pakistan have already signed a multi-billion-dollar deal to construct an Economic Corridor through AJK connecting Kashgar with Gwadar by improving the existing Karakorum road link, though analysts in China questioned its feasibility in view of present conditions.

According to Chinese officials, the new rail link, which runs through the Pamir Plateau and Karakorum mountains, will be one of the hardest to build.