Step 1: The 1950 Treaty of Peace and Friendship (The Open Border)
The cornerstone of bilateral ties is the historic Indo-Nepal Treaty of Peace and Friendship of 1950. This exceptional treaty establishes an “open border” between the two sovereign nations. It legally permits the citizens of both countries to cross borders without passports or visas, travel freely, acquire property, reside, and seek employment in each other's countries. Millions of Nepali nationals live and work in India, enjoying equal civil privileges.
Step 2: Civilizational, Cultural, and Familial Ties (Roti-Beti Ka Rishta)
India and Nepal share an ancient, deeply intertwined civilizational heritage. Bound by shared religious traditions (Hinduism and Buddhism), language, script, and folklore, the two populations share deep-rooted bonds. This close-knit relationship is popularly referred to as “Roti-Beti ka Rishta” (ties of livelihood and marriage), particularly evident along the open borders of Uttar Pradesh and Bihar, where cross-border marriages are common.
Step 3: Economic and Trade Transit Interdependence
Nepal is a landlocked Himalayan nation. Under international transit treaties, India provides Nepal with critical trade corridors and sea-port access (at Kolkata and Visakhapatnam) to conduct trade with the rest of the world. India is Nepal's largest trading partner and biggest foreign investor. Additionally, the joint development of Nepal's massive Himalayan run-of-the-river hydropower potential provides clean energy to India's power grid while boosting Nepal's national economy.
Step 4: Defence Cooperation and Humanitarian Assistance
The national security of India and Nepal is closely linked. The two militaries share a unique bond; the Indian Army recruits soldiers from Nepal into its famous Gorkha Regiments. The armies conduct a regular joint military exercise called Surya Kiran. Furthermore, India is always the first responder during natural crises in Nepal, as demonstrated by the extensive rescue, relief, and financial reconstruction aid worth billions of rupees provided by India following the devastating Nepal earthquake of April 2015.