India and China signed Border Defence Cooperation Agreement (BDCA). The agreement on the Line of Actual Control (LAC) involves:
1,2 and 4 only
Border Defence Cooperation Agreement was signed after the PLA’s Ladakh intrusion. It rests on the premise that one side will not follow or tail patrols of the other side in border areas where there is no common understanding. Thus, Indian side has to physically monitor the entire LAC and without leaving any gaps. This has put pressure on manpower, annual
defence spending and military modernisation. PLA vacated Depsang only when New Delhi agreed to sign the BDCA. India has now reduced its patrolling limit in Depsang which has resulted in a new de facto LAC
The two sides shall implement border defence cooperation in the following ways: