(1) No Bill or amendment which imposes or varies any tax or duty in which Provinces are interested or which varies the meaning of the expression "agricultural income" as defined for the purposes of the enact-ments relating to Indian income-tax, or which affects the principles on which under any of the foregoingprovisions if this chapter moneys are or may be distributable to Provincesor States, or which imposes any such Federal surcharge as is mentioned inthe foregoing provisions of this chapter, shall be introduced or moved ineither Chamber of the Federal Legislature except with the previous sanctionof the Governor-General in his discretion.

(2) The Governor-General shall not give his sanction to the introduction of any Bill or the moving if any amendment imposing in any year any such Federal surcharge as aforesaid unless he is satisfied that all practicable economies and all practicable measures for otherwise increasing the proceeds of Federal taxation or the portion thereof retainable by the Federation would not result in the balancing of Federal receipts and expenditure on revenue account in that year.

(3) In this section the expression "tax or duty in which Provinces are interested" means--

(a) a tax or duty the whole or part of the net proceeds whereof are assigned to any Province; or

(b) a tax or duty by reference to the net proceeds whereof sums are for the time being payable out of the revenues of the Federation to any Provinces.