Landlocked Nepal is overwhelmingly reliant upon imports from India, including much of its food, consumer goods, and 100 percent of its fuel – aviation fuel, petrol, diesel and cooking gas.

India’s unofficial blockade of Nepal – now in its third week – has, therefore, crippled life in this country of 30 million people. Things could get a lot worse.

India denies that there is a blockade, and there is some room for ambiguity. But the Indian Oil Corporation’s refusal to service Nepali tankers, and the candid comments of officials on the border, make the situation clear enough.

The crisis can be traced back to early August, when residents of Nepal’s southern plains bordering India, who are known as Madhesis, began protesting provisions of the country’s new constitution, which was then being rushed to completion in a “fast-track” process.

Madhesis, who comprise around 30 percent of the population, objected to the proposed new federal boundaries, to provisions that they said would lead to their underrepresentation in the national parliament, and to the dilution of provisions which they hoped would lead to more equitable representation in public employment and official positions.

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Madhesi groups argued that the constitution was being written in abrogation of previous agreements, and without consulting them. Around 45 people, including policemen, were killed in protests.

A strike imposed in southern Nepal has now been in effect for over 50 days. Much of the country has therefore been crippled for almost two months.

The constitution was passed on September 20, by a vote in the elected assembly. The government argues that it is democratic and denies that it discriminates against Madhesis. New Delhi nevertheless reacted furiously.

India has had an influential role in Nepali politics since the time of the British Raj. In recent years the southern neighbour played a crucial role in guiding and guaranteeing the country’s 10-year peace process, of which the new constitution was a central part.

However, after Narendra Modi was elected as prime minister of India in 2014, Delhi stepped back from its previous micro-management, largely limiting itself to public statements that the constitution should accommodate all sections, and signing a $1bn aid agreement.

The constitution had been all but ratified before India seemed to wake up to the political crisis that was brewing along its border.

Madhesis share strong links with communities across the border, meaning that turmoil in Nepal has domestic political as well as security implications. It is also significant that the populous neighbouring Indian state of Bihar is currently holding elections, which are crucial for Modi’s party, the BJP.

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If Delhi had intervened more artfully and earlier, it might have helped to broker a constitution that was less objectionable to Madhesis. Instead, supplies to Nepal were cut off one or two days after the constitution’s promulgation.

India blames the continuing protests in the southern part of the Himalayan nation for the fact that nothing is getting through. In reality, New Delhi’s pressure tactics rely on the fact that no one really believes that.

Besides, a blockade cannot be openly admitted because it would almost certainly be illegal and in breach of treaty obligations.

If New Delhi has miscalculated, then so has Kathmandu. The manner of the constitution’s “fast-track” promulgation precipitated a bloody domestic crisis that could easily have been avoided.

New Delhi’s signals were catastrophically misread. Kathmandu’s political class told itself that all the Modi government cared about in the constitution was diluting secularism and that India would accept a raw deal for the Madhesis in exchange for promises on commercial interests, such as hydropower development.

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Nepal’s geography, surrounded on three sides by India, with the Himalaya and the remote Tibetan region of China to the north, make it inescapably economically dependent on India.

Decades of misrule, in which short-sighted leaders have hollowed out the economy, have heightened that dependence. For example, there are power cuts of many hours a day. How will Kathmandu’s generators run without Indian diesel?

Meanwhile, Nepali politicians of all stripes have long pleaded with New Delhi to advance their personal ambitions. Many are reputed to have links with the Indian intelligence community.

The same politicians are now hoping to boost their ambitions by exploiting the groundswell of nationalist outrage, which the blockade has understandably created in Nepal.

In Kathmandu, there is scarcely any traffic on the roads, and drivers must queue four days for a small ration of fuel. Prices are rising, schools are closing, and the situation could fast deteriorate.

The government apparently hopes to buy some breathing space by declaring a two-week national holiday during the coming festival season.

The country has also scarcely begun to recover from April’s earthquake, which particularly devastated hilly districts to the north of the capital.

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The government declared ‘relief operations’ over on June 22, but the truth is that millions of people remain in desperate need of essentials such as adequate food and shelter.

The government has not yet spent a cent of the $4bn promised for reconstruction. True to form, the aftermath of the earthquake has been disgracefully neglected by the government. The blockade can only deepen the survivors’ plight.

The earthquake in Nepal left at least half-a-million people homeless [Getty Images]

Despite its bad luck, and the bullying tactics of its giant neighbour, Nepal’s problems are severely exacerbated, if not entirely created, by its own rulers.

Yet, as with earthquake relief, there is little sign of urgency from the government in seeking a negotiated solution to the political causes of the blockade.

Meanwhile, the blockade is grist to the mill of those in Kathmandu who like to believe that the unpopularity of the constitution in the plains is not a “genuine” domestic issue, but a foreign conspiracy.

In truth, even when, sooner or later, the Indian blockade is lifted, Nepal’s alarming domestic fault lines will remain. And the memory of India’s crude intervention will cloud Nepali politics for years to come.