51. In addition to the interest payable under section 50, the operator liable to make a payment under section 46 shall pay interest, on any payment or part of a payment he has not made, at the rate fixed by regulation, for the period extending from the date of expiry of the delay for making payment to the day of payment or to the day when he becomes liable to pay interest under section 50, whichever is earlier; however, the Minister is authorized to compensate in whole or in part the interest paid under this section for a fiscal year by applying the same rate to the excess payments.