The Centre has asked the state governments not to come up with infrastructure projects in the coal bearing areas of the country. In a letter to chief ministers of Andhra Pradesh, Jharkhand, Orissa, Chhatisgarh, Madhya Pradesh, Maharashtra and Uttar Pradesh, Coal Minister Sriprakash Jaiswal said yesterday that coal reserves in the country should not be sterilized by raising large superstructures in the areas where coal is in abundance. He said the government is making all efforts to increase coal production in the country to bridge the gap between demand and supply.