Notwithstanding the provisions of section 3, a supply of the following goods shall be charged to tax at the rate of zero per cent:

(a)  goods exported, or the goods specified in the Fifth Schedule;

(b)  supply of stores and provisions for consumption aboard a conveyance proceeding to a destination outside Pakistan as specified in section 24 of the Customs Act, 1969; and

Provided that nothing in this section shall apply in respect of a supply of goods which –

(i)  are exported, but have been or are intended to be re-imported into Pakistan; or

(ii) have been entered for export under Section 131 of the Customs Act, 1969 (IV of 1969), but are not exported; or

(iii) have been exported to a country specified by the Federal Government, by Notification in the official Gazette :

Provided further that the Federal Government may, by a notification in the official Gazette, restrict the amount of credit for input tax actually paid and claimed by a person making a zero-rated supply of goods otherwise chargeable to sales tax.