From facilitating close people-to-people ties to being a preferred route of Islamic fundamentalists and smugglers: How an open India-Nepal border poses a challenge for India

India’s neighbouring country Nepal has been going through a phase of political instability for the past few days. The country’s leaders, including the President and the Prime Minister, not only had to resign but also had to take refuge under the protection of the army. All this was triggered by a ban on social media, and gradually spread to issues like corruption, nepotism and economic crisis. More than 19 people were killed in the ‘Gen Z’-led protests and violence in Nepal.

Amidst the chaos in Nepal, the India-Nepal relations have also become a talking point. Actually, the border between India and Nepal is not just a line, but a symbol of centuries-old relations. There is a bond of roti-beti (food and marriage), cultural similarities and a mutual connection in the everyday lives of the people of the two countries. But these relations are now facing new challenges. Threats of smuggling, crime, infiltration and terrorism endanger the open border. In this report, we explain the India-Nepal relations in detail.

India and Nepal are bound by the Treaty of Sugauli

India and Nepal share an approximately 1,751 km long border, which passes through five Indian states – Sikkim, West Bengal, Bihar, Uttar Pradesh and Uttarakhand. It is spread over 99 km in Sikkim, 100 km in West Bengal, 729 km in Bihar, 560 km in Uttar Pradesh and 263 km in Uttarakhand. The border is mostly open, that is, there is no big wall or fencing, which allows the people of both the countries to move freely across the border. But the open border poses a challenge for national security.

The story of India-Nepal border begins with the Anglo-Nepal War of 1815-16, which was fought between Nepal’s Gorkha army and the British East India Company. Nepal was defeated in the war, and the Treaty of Sugauli was signed on 2 December 1815, which came into force on 4 March 1816. This treaty handed over one-third of Nepal’s territory to British India, including most of the Terai region. The treaty fixed the Kali River (Mahakali) as the western border of Nepal, which is still a matter of dispute.

What were the main provisions of the Treaty of Sugauli?

First, Nepal had to hand over about one-third of its land to British India, which included a large part of the Terai region, Kumaon-Garhwal, Simla Hills, Sikkim and Darjeeling. Nepal’s western border was determined by the Mahakali River (Kali River), the eastern border by the Mechi River. Nepal had to limit its army to just 12,000 soldiers. In addition to that, the British kept the right to keep a Resident (representative) in Kathmandu, who kept an eye on Nepal’s internal affairs.

Nepal was compelled to establish trade relations with the British and follow British advice in foreign policy. The Himalayan country had to give the Terai region between the Koshi and Gandak rivers to the British in the treaty, but later, in 1816, through an additional treaty, Nepal got some part of the Terai region back. However, it still remains a matter of dispute.

This treaty decided the border, but it had many flaws. The changing course of the rivers and forests made the border unclear. The result was that many villages and fields were divided. For example, houses of people fell within the Indian side, while their fields were included in Nepal. In several bordering areas, joint families were divided by the border. In areas like Susta and Kalapani, the border is still disputed, where the changing flow of the river has complicated the border demarcation. The maps were made by the British officials at the time of the treaty, but they were far from accurate.

After independence, the treaty of Sugauli formed the basis of the Indo-Nepal Peace and Friendship Treaty of 1950, but the border issues remain to date. Both countries continue to negotiate the border issues, which have not been completely resolved. Political pressure on either side poses a challenge in resolving the border issues.

Bihar is most affected, and Rot-beti relationships are very important

The largest part of the India-Nepal border touches Bihar, which is about 729 km long. The people here are so close to the Terai region of Nepal that it is called ‘Roti-Beti ka Rishta‘, as they share food, culture and have marital relations. The language is also similar – a mixture of Maithili, Bhojpuri and Nepali. The people living in the Terai region of Nepal are culturally very close to the people of Bihar.

This connection is evident in their everyday life. Nepalese people come to India for treatment, as there are few health facilities in Nepal. Nepalese patients visit hospitals in Bihar. Trade is also brisk – vegetables, grains and daily supplies move across the border. Marriages take place on both sides, which connect families. But in recent years, these ties have been weakening.

Any problem in Nepal affects the Indian farmers, who have their fields on the other side. The farmers have to cross the border to reach their farms, which becomes difficult during such times. There are many farmers who have their homes in India, but their fields and barns are in Nepal. They have been farming their lands for years, but now that the security along the India-Nepal border has been tightened, they are finding it difficult to cross the border.

Farmers have to go through hours of interrogation to reach their farms. Even tractors and bullock carts are not allowed, which is creating a lot of problems in harvesting, bringing crops and sowing crops. On top of that, the Nepalese government has tightened the rules for land sale. As per the rules, Indian farmers can sell their land only to Nepali citizens and that too at a low price.

Infiltration from Nepal is also a big issue

There have been reports of encroachment by Nepali citizens in the Indian border areas, especially in Bihar’s Sitamarhi, Madhubani and Supaul districts. According to media reports, Nepali people are occupying Indian land and obtaining important documents like Aadhar card, PAN card, ration card and voter ID by forging documents. These people are taking advantage of government schemes meant for Indian citizens.

The reports state that such activities are rampant in the border villages adjacent to Nepal. Many Nepalese citizens settle in India on the pretext of marriage and forge documents with the connivance of local officials. This increases the threat to India’s security and border integrity. The local administration and police take action in several cases, but the problem is still serious. The current situation in Nepal has further complicated the India-Nepal border dispute, especially in areas under the Sugauli Treaty.

Why is there no fencing on the India-Nepal border?

Why is there no fencing on the India-Nepal border? The reason is simple – the people living on both sides of the border have close ties. If a wall is built along the India-Nepal border, their relationships as well as everyday life will be impacted. Governments of both countries believe that the open border is a symbol of friendship between the two countries. But an open border poses a unique set of challenges. In the 1970s and 80s, items like sugar, clothes, etc. used to get passed through the border, but now smuggling of gold, narcotics, weapons and even human trafficking has become a cause of concern for the security forces.

The biggest threat to the India-Nepal border comes from Pakistan’s ISI. The ISI has been using Nepal for anti-India activities. Infiltration is easy through Nepal’s open border, which is why the ISI has set up bases in Nepal, where conspiracies are hatched to spread terrorism in India. Terrorists from organisations like Lashkar-e-Taiba, Khalistan and Jaish-e-Mohammed come to India through the Nepal route. Recently, Delhi Police arrested a Nepali citizen who was supplying Indian SIM cards to ISI.

The case of former Nepal MP Mohammad Aftab Alam presents a perfect example of the problems created by an open border. Alam, a leader of the Nepali Congress, was accused of being an ISI agent and killing many people in a bomb blast in Rautahat in 2008. Investigation revealed that he burnt people alive during an election violence. He was sentenced to life imprisonment in 2024, but was acquitted by the High Court in 2025. This case shows how political people in Nepal can be associated with foreign forces, which is a threat to India’s security.

Conversion and demographic change are a big threat to India

Another emerging problem at the Nepal border is that of religious conversion. The Islamic population in Nepal is increasing rapidly, especially in the Terai region. Reports suggest that mosques are being built with foreign funding, especially Pakistani funding, and the Hindus are being converted. This is a threat to India’s security, as the increase in the Muslim population on both sides of the border can spread fundamentalism.

Nepal had a Hindu majority society, but many Islamic organisations have become active in the country over the years. They have been demanding the right to slaughter cows and eat beef. This effect is also visible in the border areas of India, where demographic imbalance is challenging national security.

Political turmoil affects the border

Political instability in Nepal has a direct impact on India. Violence broke out during the Gen Z demonstration in Nepal, in which over 19 people were killed. Due to this, security has been increased on the India-Nepal border. Trade is getting affected as India’s imports worth $7.32 billion to Nepal may stop. The instability in Nepal is indirectly affecting India’s interests.

(This article is a translation of the original article published in OpIndia Hindi.)