(1) The countervailing duty levied under rules 15 and 20 shall take effect from the date of publication of the notification in the Official Gazette.

(2) Notwithstanding anything contained in sub-rule (1) -

(a) where a provisional duty has been levied and where the designated authority has recorded a finding of injury or where the designated authority recorded a finding of threat of injury and a further finding that the subsidised imports, in the absence of provisional duty would have led to injury, the countervailing duty may be imposed from the date of imposition of provisional duty:

(b) in the circumstances referred to in sub-section (4) of section 9 of the Act, the countervailing duty may be levied retrospectively from the date commencing ninety days prior to the imposition of provisional duty:

Provided that in case of violation of an undertaking referred to in sub-rule (6) of rule 17, no duty shall be levied retrospectively on imports which have entered for home consumption before violation of such terms of the undertaking.