Coal India is set to begin a roadshow to promote what is expected to be India’s biggest stock listing, even as tightened environmental regulations and a Maoist insurgency threaten to render much of the state-owned miner’s reserves inaccessible.

The company’s biggest coal fields are located in remote regions dominated by Maoist rebels who often target business activities for extortion, disrupt roads and railway lines used to transport coal and are suspected of involvement in coal theft.

Moreover, the coal ministry has yet to persuade Manmohan Singh, the prime minister, to roll back an order by the environment ministry that this year designated areas covering about 40 per cent of Coal India’s reserves as “no-go areas” for mining to stop the wholesale felling of eastern forests.