When the mortgagor or such other person as aforesaid has tendered or deposited in Court under section 83 the amount remaining due on the mortgage, interest on the principal money shall cease from the date of the tender or ¹[in the case of a deposit, where no previous tender of such amount has been made], as soon as the mortgagor or such other person as aforesaid has done all that has to be done by him to enable the mortgagee to take such amount out of Court, ²[and the notice required by section 83 has been served on the mortgagee:
     Provided that, where the mortgagor has deposited such amount without having made a previous tender thereof and has subsequently withdrawn the same or any part thereof, interest on the principal money shall be payable from the date of such withdrawal].
     Nothing in this section or in section 83 shall be deemed to deprive the mortgagee of his right to interest when there exists a contract that he shall be entitled to reasonable notice before payment or tender of the mortgage-money ³[and such notice has not been given before the making of the tender or deposit, as the case may be.]