Interest on amount of enhanced assessment or of refund.

If, as a result of an order passed in appeal under section 124G, the assessment is enhanced and any amount of difference is required to be recovered from the appellant or any amount from out of the amount paid under clause (b) of section 124H is required to be refunded to the appellant, an interest at the rate of eighteen per cent. per annum shall be payable,-

1. (a) in the case of amount to be so recovered, from the date of the notice of original assessment till the date of recovery thereof; and
2. (b) in the case of amount to be so refunded, from the date on which the amount was paid under clause (b) of section 124H till the date of refund thereof.