(1) Where a registered dealer, or a dealer required to furnish return under sub-section (3) of section 30, furnishes return in respect of any return period but fails to make full payment of the tax payable under sub-section (4) of that section in respect of any tax period within such return period by the prescribed date for payment of tax, he shall pay a simple interest at the rate of twelve per centum per annum for the period commencing on the date immediately following the prescribed date for payment of tax and upto the date prior to the date of payment of such tax or, upto the date preceding the date of commencement of proceeding under section 52 or, upto the date prior to the date of assessment under section 45, or section 46, as the case may be, whichever is earlier, in respect of such return period upon so much of the amount of tax payable by him according to such return as remains unpaid:

Provided that where such dealer admits in writing that the amount of tax payable in respect of any such tax period within the return period is an amount which is either more or less than what has been originally shown as payable in the return and where the Commissioner is satisfied on the point of such admission, the interest shall be payable upon so much of the amount of tax payable for such tax period according to such admission as remains unpaid.

(2) Where a registered dealer, or a dealer required to furnish return under sub-section (3) of section 30, fails to furnish such return by the prescribed date or thereafter in respect of any return period before the assessment under section 45, or section 46, as the case may be, and on such assessment full amount of net tax payable for such period is found not to have been paid by him by the prescribed date for payment of tax, he shall pay a simple interest at the rate of twelve per centum per annum for the period commencing on the date immediately following the prescribed date of payment of such tax in respect of such tax period and upto the date prior to the date of assessment under section 45, or section 46, as the case may be, in respect of such return period upon so much of the amount of tax payable by him according to such assessment as remains unpaid:-

Provided that where the assessment under section 45, or section 46, as the case may be, is made for more than one return period and such assessment does not show separately the tax payable for the tax periods within such return periods in respect of which interest is payable under this sub-section, the Commissioner shall apportion the tax payable for the tax periods within such return periods on the basis of such assessment.

(3) A dealer liable to pay interest under sub-section (1) or sub-section (2) of this section or sub-section (8) of section 40, as the case may be, shall, in the prescribed manner, pay into a Government Treasury or the Reserve Bank of India the amount of interest payable by, or due from, him by such date as may be prescribed.

(4) Interest under sub-section (1) or sub-section (2) of this section shall be payable in respect of the returns, the prescribed dates for furnishing of which under sub-section (2) or sub-section (3) of section 30 are the dates subsequent to the appointed day.