The government has accorded in-principle approval for setting up 21 Greenfield Airports across the country so far. Minister of State for Civil Aviation Dr. V. K. Singh said this in a written reply to a question in Rajya Sabha today. He said, the government has formulated a Greenfield Airport Policy, 2008 which provides Guidelines for the establishment of new Greenfield Airports in the country. Dr. Singh said, Airports Authority of India has taken up development of new airports and up-gradation of existing airports at an estimated cost of around 25 thousand crore rupees in the next 4 to 5 years.