NEW DELHI: The Centre today advised states not to build mega projects in coal-bearing areas, afraid that such a move would "sterilise" at least 20 billion tonnes of the dry-fuel reserves and aggravate coal shortage in the country.

"We have asked Chief Ministers of coal-bearing states to not to allow large super structures or expansion projects on coal-bearing areas, as this would steelies at least 20 billion tonnes of reserves," Coal Minister Sriprakash Jaishwal said.