Context: The skirmishes and the standoff between Indian and Chinese troops at Naku La in Sikkim last month, in an area of the Line of Actual Control (LAC) has highlighted the historical Sikkim-Tibet Convention of 1890 which is a proof of India’s ownership of the territory.
Background
Anglo-Chinese Convention of 1890

• That treaty, called the “Convention between Great Britain and China relating to Sikkim and Tibet”, essentially paved the way for the colonial power to annex the small state of Sikkim.
• Under the Anglo-Chinese Convention of 1890, the Sikkim-Tibet border was agreed upon and in 1895 it was jointly demarcated on the ground.

The treaty’s first article has been particularly highlighted by Chinese officials

• “The boundary of Sikkim and Tibet shall be the crest of the mountain range separating the waters flowing into the Sikkim Teesta and its affluents from the waters flowing into the Tibetan Mochu and northwards into other rivers of Tibet. The line commences at Mount Gipmochi, on the Bhutan frontier, and follows the above-mentioned water-parting to the point where it meets Nepal territory,” Article 1 said.
• The second article recognized the British government’s control over Sikkim.
• “It is admitted that the British Government, whose Protectorate over the Sikkim State is hereby recognised, has direct and exclusive control over the internal administration and foreign relations of that State, and except through and with the permission of the British Government, neither the Ruler of the State nor any of its officers shall have official relations of any kind, formal or informal, with any other country,” the treaty said.

China’s acceptance of Sikkim as integral to India

• The new government of the People’s Republic of China, which took power in 1949, confirmed this position in a formal note to the Government of India in 1959.
• Agreement on this alignment was reiterated in the 2003 Sino-Indian agreement to promote trade between Sikkim and Tibet via Nathu La. China has also formally recognized Sikkim as an integral part of India.

Issue Area

• The meetings between former Prime Minister Atal Bihari Vajpayee and Chinese Premier Wen Jiabao in 2003 and maps exchanged subsequently indicated that India recognised the Tibetan Autonomous Region as a part of China, and Beijing recognised Sikkim as a State of the Indian Union, the boundary at Sikkim while undisputed, remains undemarcated on the ground.
• China may now be opening up a front in Sikkim due to the ambiguous official position of the boundary.
• In 2017, after the Doklam stand-off near the India-Bhutan-China trijunction, the then Foreign Secretary S Jaishankar informed the Parliamentary Standing Committee that India accepted the 1890 treaty as “the basis for alignment”, but the treaty had only been “partially implemented on the ground”.

Associated Concern

• Hidden Chinese agenda: Diplomatic experts point out that China may also be opening up a front in Sikkim due to the ambiguous official position of the boundary.
• With a perceptible shift in that stand, and incidents of more intrusive patrols by the PLA, experts surmise that not only will the two sides need to negotiate to resolve the stand-off at Naku La, but New Delhi should also have more diplomatic focus on laying down the line firmly to Beijing on the boundary in Sikkim.