Forieng ministry claimed that the evidence is recognised by the Bhutan side. (Photo: Representational/PTI)

Beijing: China on Friday said the diplomatic channels with India are "unimpeded" for talks over the stand-off in the Sikkim sector but for any "meaningful dialogue" the Indian troops must withdraw from the Doklam area over which Beijing has "indisputable sovereignty".

"The diplomatic channels for the communication between Chinese and Indian sides remained unimpeded," Chinese Foreign Ministry spokesman Lu Kang told media briefing here.

He said the Indian troops "trespassed" the recognised delineated boundary between China and India on June 18. This is the first time China came out thewith precise date about Indian troops entering the disputed Doklam area (referred by China as Donglong) near Sikkim allegedly to stop Chinese troops from constructing a road.

"So the most pressing issue should be the withdrawal of troops into the Indian territory. So it is the pre-condition for any meaningful dialogue," he said when asked whether any talks were going on between the two countries over the issue.

He said in additions to the photographs of alleged Indian "incursion" into Donglong area, the Chinese foreign ministry will also upload a map on its website to provide a "better understanding of the reality".

He also refuted Bhutan's allegation that Chinese troops' attempts to build the road violated the 1988 and 1999 agreements to maintain peace and tranquilly.

Lu said China has "indisputable sovereignty over the Donklam area." He claimed that the Doklam area was under Chinese administration from emperor Qing dynasty, the last imperial dynasty of China established in 1636.

Lu said the area where Chinese side undertook road construction "totally belongs to the Chinese territory" and offered to release details on this on foreign ministry's website.

"From historical evidence we can see that Doklam has been a traditional pasture for the Tibetan residents and we have exercised good administration over the area," he said.

Before the 1960s, if the Bhutan residents around the border wanted to graze their cattle they had to get the approval from China, he said. "The Tibetan dynasty and Qing dynasty also set a clear boundary along the border," he said.

"In addition to the jurisprudential evidence, the historical convention in 1890 (the Sinio-British treaty) has clearly defined it as the crossing point between China, Bhutan and Indian boundary.

"The Doklam area belongs to Chinese territory and we are exercising complete and comprehensive administration over the the region and our border troops and the residents around the border are herding their cattle along this," he said.

He claimed that the evidence is recognised by the Bhutan side. "Even though China and Bhutan have not established diplomatic relationship we always maintain traditional friendship. We can tell you that Chinese people are friendly and want good relations with Bhutan people," he said.

"But our determination to uphold our territorial integrity and sovereignty is unwavering," he said. A standoff erupted between the two militaries after the Indian Army blocked construction of the road by China in Doklam, a disputed territory between China and Bhutan also known as Donglong.