India is set to reinforce its northeastern frontier by adding railway infrastructure to deepen access, accelerate logistics and ensure military readiness in case warming ties with neighboring China falter again.

The approved plan involves laying 500 kilometers (about 310 miles) of rail lines, including bridges and tunnels, to connect remote regions bordering China, Bangladesh, Myanmar and Bhutan, according to people familiar with the matter.

The project, which will likely cost the government 300 billion rupees ($3.4 billion), is expected to be completed within four years, said the people, who asked not to be identified as the information is not public.

Though ties with China have recently shown signs of warming, India’s infrastructure strategy reflects long-term contingency planning that’s mindful of a decades-old relationship marked by cycles of rapprochement and strain. Five years after a border clash, the neighbors have recently been mending fences, drawn together by economic opportunity and shifting trade dynamics under U.S. President Donald Trump.

India’s new rail corridors will complement extensive road infrastructure built over the past decade. The country has added 9,984 kilometers of highways at a cost of 1.07 trillion rupees, with another 5,055 kilometers under construction.

The logistics upgrade is expected to improve civilian access and reduce response times during emergencies, including natural disasters or military mobilizations.

Landing Ground

India has also reactivated airside infrastructure such as Advance Landing Grounds — which have been dormant since 1962 — for helicopter and military aircraft use in its northeastern territories, the people said.

Discussions are also underway to study additional rail lines near the disputed border with China in the northern Ladakh region, they said. The current network extends to Baramulla in Kashmir Valley, a region contested by both India and Pakistan.

The Indian Railways and the government’s Press Information Bureau didn’t immediately respond to emailed requests for comment.

Prime Minister Narendra Modi has prioritized connectivity in sensitive zones, including 1,450 kilometers of new roads along the Pakistan border and upgrades near Doklam, a plateau near the Indian border that is claimed by both China and Bhutan. Earlier this year, he inaugurated the world’s tallest railway bridge connecting the Kashmir Valley with the rest of the country.

India has separately constructed 1,700 kilometers of rail lines in the northeastern region in the past decade, the people said.

The latest effort is part of a broader strategy to reduce troop mobilization time and reinforce logistical depth, they said.

China, meanwhile, has accelerated its own buildout since an earlier 2017 military stand-off over Doklam, constructing dual-use infrastructure such as airports and heliports. Its expansion has bolstered the People’s Liberation Army’s logistics capabilities through faster equipment and troops movement.