South Tibet dispute

Sovereignty over two large and various smaller separated pieces of territory have been contested between China and India. The westernmost, Aksai Chin, is claimed by India as part of the state of Jammu and Kashmir and region of Ladakh but is controlled and administered as part of the Chinese autonomous region of Xinjiang. It is an uninhabited region at high altitude crossed by the Xinjiang-Tibet Highway. The other large disputed territory, the easternmost, lies south of the McMahon Line. It was formerly referred to as the North East Frontier Agency, and is now called Arunachal Pradesh. The McMahon Line was part of the 1914 Simla Convention between British India and Tibet, an agreement rejected by China.

The 1962 Sino-Indian War was fought in both of these areas. An agreement to resolve the dispute was concluded in 1996, including "confidence-building measures" and a mutually agreed Line of Actual Control. In 2006, the Chinese ambassador to India claimed that all of Arunachal Pradesh is Chinese territory amidst a military buildup. At the time, both countries claimed incursions as much as a kilometre at the northern tip of Sikkim. In 2009, India announced it would deploy additional military forces along the border. In 2014, India proposed China should acknowledge "One India" policy to resolve the border dispute.

In 1960, based on an agreement between Nehru and Zhou Enlai, officials from India and China held discussions in order to settle the boundary dispute. China and India disagreed on the major watershed that defined the boundary in the western sector. The Chinese statements with respect to their border claims often misrepresented the cited sources.

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