Further, out of 50 explored blocks, project reports of 25 blocks have been prepared, the coal ministry was informed.
The ministry "emphasised on quick operationalisation of all of these blocks, otherwise CIL may return them to the Ministry of Coal for their allotment/ auction to other agencies," the official said.
Coal India Ltd (CIL) accounts for over 80 per cent of domestic coal output.
The state-owned firm had earlier said that it will produce 750 million tonnes of coal in the next financial year.
The PSU will further produce 1 billion tonnes of coal by FY2024, Coal Minister Pralhad Joshi had said.
CIL is targeting to produce 660 million tonnes of the dry fuel in 2019-20 compared to 607 million tonnes in the last fiscal.