(1) If a registered dealer fails, without sufficient cause, to pay the amount of tax due as per the return furnished under rule 7 or fails to furnish a return under these rules, such dealer shall be liable to pay interest in respect of the tax, which he fails to pay according to the return or the tax payable for the period for which he failed to furnish return, at the rate of one per centum per month from the date the return for the period was due to the date of its payment or to the date of order of assessment, whichever is earlier.

(2) Every dealer required to pay interest under sub-rule (1) shall pay such interest at the time of making payment of the tax, or on the date specified in the demand notice as per the order of assessment, whichever is earlier.

(3) The dealer shall furnish a statement showing details of calculation of the amount of interest payable as referred to in sub-rule (1) and furnish such statement alongwith the receipted challan or crossed demand draft or banker' cheque evidencing payment of such interest.