Published on: March 18, 2023

McMahon Line

McMahon Line

Why in news? Two United States Senators, a Republican and a Democrat, have introduced a bipartisan resolution in the upper chamber of Congress reiterating that the US recognises the McMahon Line as the international boundary between China and India in Arunachal Pradesh.


  • This decision will enhance the US-India strategic partnership and the Quad in support of the Free and Open Indo-Pacific.
  • The resolution reaffirms India’s well-known and established position that Arunachal Pradesh, which China calls ‘South Tibet’, is an integral part of India

What is the McMahon Line?

  • The McMahon Line serves as the de facto boundary between China and India in the Eastern Sector.
  • It specifically represents the boundary between Arunachal Pradesh and Tibet, from Bhutan in the west to Myanmar in the east.
  • China has historically disputed the boundary and claims the state of Arunachal Pradesh as part of the Tibetan Autonomous Region (TAR).

Under what circumstances was it drawn?

  • The McMahon Line was drawn during the Simla Convention of 1914, officially described as the Convention Between Great Britain, China, and Tibet.
  • The McMahon Line delimited the respective spheres of influence of Tibet and British India in the eastern Himalayan region in what is today India’s Northeast and northern Myanmar.
  • The border in this region was undefined prior to the signing of the convention.

What happened at the Simla Convention of 1913-14?

  • The convention attempted to settle the question of Tibet’s sovereignty and avoid further territorial disputes in the region.
  • The treaty divided the Buddhist region into “Outer Tibet” and “Inner Tibet” – the former would remain in the hands of the Tibetan Government at Lhasa under Chinese suzerainty(China was not allowed to interfere in its affairs.
  • The latter( inner Tibet) would be under the direct jurisdiction of the newly formed Republic of China.
  • In its annexes, it also determined the border between China proper and Tibet as well as Tibet and British India.
  • The latter of these newly decided boundaries would later be called the McMahon Line after McMahon, the chief British negotiator.

What has the status of the McMahon line been since 1914?

  • While there were disputes regarding the McMahon line from the very beginning, after the communists took power in 1949, they pulled China out of all international agreements and the so-called “unequal treaties” that had been imposed on it during its “century of humiliation”, and demanded a renegotiation of all its borders.