(1) The safeguard quantitative restrictions imposed under rule 10 shall be for such period of time as may be necessary to prevent or remedy serious injury and to facilitate adjustment.

(2) Notwithstanding anything contained in sub-rule (1), safeguard quantitative restrictions imposed under rule 10 shall, unless revoked earlier, cease to have effect on the expiry of four years from the date of its imposition:

Provided that if the Central Government is of the opinion that the domestic industry has taken measures to adjust to such serious injury or threat thereof and it is necessary that the safeguard quantitative restrictions should continue to be imposed, to prevent such serious injury or threat and to facilitate adjustments, it may extend the period beyond four years:

Provided further that in no case the safeguard quantitative restrictions shall continue to be imposed beyond a period of ten years from the date on which such restrictions were first imposed.