Amendment of exemption threshold raises customs exemption under section 25(1) in public interest to a higher monetary ceiling. Exercising powers under section 25(1) of the Customs Act, 1962, the Central Government substitutes the previously specified monetary amount in Notification No. 207/89-Customs with a higher amount, stating the change is necessary in the public interest; the amendment solely replaces the exempt amount without modifying other provisions of the principal notification.