Линия фактического контроля между Китаем и Индией

Disputed boundary between China and India

The Line of Actual Control (LAC), in the context of the Sino Indian border dispute, is a notional demarcation line
that separates Indian controlled territory from Chinese controlled territory. The concept was introduced by Chinese premier Zhou Enlai in a 1959 letter to Jawaharlal Nehru as the "line up to which each side exercises actual control", but rejected by Nehru as being incoherent. The LAC is different from the borders claimed by each country in the Sino Indian border dispute. The Indian claims include the entire Aksai Chin region and the Chinese claims include Zangnan (South Tibet)/Arunachal Pradesh. These claims are not included in the concept of "actual control". The LAC is generally divided into three sectors:
the western sector between Ladakh on the Indian side and the Tibet and Xinjiang autonomous regions on the Chinese side. This sector was the location of the 2020 China–India skirmishes. the middle sector between Uttarakhand and Himachal Pradesh on the Indian side and the Tibet autonomous region on the Chinese side. the eastern sector between Zangnan (South Tibet)/Arunachal Pradesh on the Indian side and the Tibet autonomous region on the Chinese side. This sector generally follows the McMahon Line. The term "line of actual control" originally referred only to the boundary in the western sector after the 1962 Sino Indian War, but during the 1990s came to refer to the entire de facto border.

The term "line of actual control" is said to have been used by Chinese Premier Zhou Enlai in a 1959 note to Indian Prime Minister Jawaharlal Nehru. The boundary existed only as an informal cease fire line between India and China after the 1962 Sino Indian War. In 1993, India and China agreed to respect of the 'Line of Actual Control' in a bilateral agreement, without demarcating the line itself. In a letter dated 7 November 1959, Zhou proposed to Nehru that the armed forces of the two sides should withdraw 20 kilometres from the so called McMahon Line in the east and "the line up to which each side exercises actual control in the west". Nehru rejected the proposal stating that there was complete disagreement between the two governments over the facts of possession:
blockquote|It is obvious that there is complete disagreement between the two Governments even about the facts of possession. An agreement about the observance of the status quo would, therefore, be meaningless as the facts concerning the status quo are themselves disputed. Zhou responded that the LAC was "basically still the line of actual control as existed between the Chinese and Indian sides on 7 November 1959. To put it concretely, in the eastern sector it coincides in the main with the so called McMahon Line, and in the western and middle sectors it coincides in the main with the traditional customary line which has consistently been pointed out by China." The term "LAC" gained legal recognition in Sino Indian agreements signed in 1993 and 1996. The 1996 agreement states, "No activities of either side shall overstep the line of actual control." However, clause number 6 of the 1993 Agreement on the Maintenance of Peace and Tranquility along the Line of Actual Control in the India China Border Areas mentions, "The two sides agree that references to the line of actual control in this Agreement do not prejudice their respective positions on the boundary question". The Indian government claims that Chinese troops continue to illegally enter the area hundreds of times every year, including aerial sightings and intrusions. In 2013, there was a three week standoff (2013 Daulat Beg Oldi incident) between Indian and Chinese troops 30 km southeast of Daulat Beg Oldi. It was resolved and both Chinese and Indian troops withdrew in exchange for an Indian agreement to destroy some military structures over 250 km to the south near Chumar that the Chinese perceived as threatening. In October 2013, India and China signed a border defence cooperation agreement to ensure that patrolling along the LAC does not escalate into armed conflict.

At the end of the 1962 war, India demanded that the Chinese withdraw to their positions on 8 September 1962 (the blue line in Map 2). Restored ambassadorial relations in 1976, a visit of the Indian Prime Minister to China in 1988, a visit of the Chinese Premier to India in 1992 and then a visit of Indian President to China in 1992 preceded the 1993 agreement. Prior to the 1993 agreement, a trade agreement was signed in 1984, followed by a cultural cooperation agreement in 1988. The 1993 agreement, signed on 7 September, was the first bilateral agreement between China and India to contain the phrase Line of Actual Control. The agreement covered force level, consultations as a way forward and the role of a Joint Working Group. The agreement made it clear that there was an "ultimate solution to the boundary question between the two countries" which remained pending. It was also agreed that "the two sides agree that references to the line of actual control in this Agreement do not prejudice their respective positions on the boundary question".

In article 10 of the 1996 border agreement, both sides agreed to the exchange of maps to help clarify the alignment of the LAC. It was only in 2001 when the first in depth discussion would take place with regard to the central/middle sectors. Maps of Sikkim were exchanged, resulting in the "Memorandum on Expanding Border Trade". However the process of exchange of maps soon collapsed in 2002–2003 when other sectors were brought up. Shivshankar Menon writes that a drawback of the process of exchanging maps as a starting point to clarify the LAC was that it gave both sides an "incentive to exaggerate their claims of where the LAC lay". On 30 July 2020, the Chinese Ambassador to India Sun Weidong stated that China was not in favour of clarifying the LAC anymore as it would create new disputes. Similar viewpoints have been aired in India that China will keep the boundary dispute alive for as long as it can be used against India. On the other hand, there have been voices which say that clarifying the LAC would be beneficial for both countries.

The Line of Actual Control is one of the settings in Neal Stephenson's novel Termination Shock, where volunteer martial artists from India and China fight to move the line in skirmishes covered on social media.