Taking exception to the visit by US envoy in India to Arunachal Pradesh which it claims as southern Tibet, China said on Monday any interference by Washington in the Sino-India boundary dispute will make it "more complicated" and "disturb" hard-won peace at the border.
Asking the US to desist from interfering in the border dispute, Chinese foreign ministry spokesperson Lu Kang told media that China is firmly opposed to the visit.
Referring to US envoy Richard Verma's October 22 tour to Tawang at the invitation of Arunachal Pradesh chief minister Pema Khandu, Lu said while replying to a question that the US envoy visited a "disputed region".
"We have also noted that the place visited by senior US diplomatic official is a disputed region between China and India. We are firmly opposed to his visit," he said.
China claims Arunachal Pradesh as part of southern Tibet and routinely protests visits by Indian leaders, foreign officials as well as the Dalai Lama to the area.
"China's position on eastern section of the boundary is very clear and consistent. The two countries are now trying to resolve territorial disputes through negotiations and consultations," he said referring to the Special Representatives mechanism headed by National Security Advisors of both countries to find a solution.
Both sides held 19th round of Special Representatives' talks to resolve the disputes over the 3,488-km Line of Actual Control (LAC).
While China claims Arunachal Pradesh as Southern Tibet and India asserts that the dispute covers Aksai Chin area which was occupied by China during the 1962 war.
Lu said "any third party with a sense of responsibility should respect efforts made by China and India for peace reconciliation? and tranquility rather than the opposite," he said.
The behaviour by the US contrasts the efforts made by China and India, he said.
"It will only make the dispute more complicated, disturb the hard-won peace and tranquility of border areas and sabotage peaceful development of the region," Lu said.
"We urge the US to stop its interference in the boundary issue between China and India and make more contribution to regional peace and stability," he said.
The boundary question between China and India is very complex and sensitive, he said adding that "the interference by a third party will only stir up or heighten tensions".
"At the end of the day only the peoples of the two countries will fall victims," he said. "We believe India and China as two major countries have enough wisdom to properly to deal with this issue and safeguard the fundamental interest of the two peoples," Lu said.