"Ammonium Nitrate is to be imported in bagged form only irrespective of the quantity in each bag on the deck of any importing vessel and packed at the point of origin," said the Home Ministry in a memorandum.
It added: "Security arrangement (two armed guards with GPS System) should be provided for security of vehicles for transportation within the country."
While the fertiliser industry consumes part of Ammonium Nitrate, the main user is the construction sector where the chemical is used for blasting.
There have been growing concerns over the misuse of the chemical.
Last month, barely a week after recovery of 100 kg of explosives in Murshidabad district, the CID had seized a huge cache of raw materials, including 600 kg of ammonium nitrate, for explosives from a godown in central Kolkata.