Deferred payment of import duty allowed for specified importers under rules; interest rates prescribed for late payment within a set range. The amendment permits the Central Government, by notification, to allow specified classes of importers to make deferred payment of import duty and charges as provided by rules; it also requires importers who fail to pay duty within the prescribed two day period (or within the deferred payment due date set by rules) to pay interest on unpaid or short paid duty until payment, at a rate fixed by the Central Government within the statutory floor and ceiling.