In which stage can the Court allow payment of court-fee if it has not been paid initially?

CPC: Section 149. Power to make up deficiency of court-fees: Where the whole or any part of any fee prescribed for any document by the law for the time being in force relating to court-fees has not been paid, the Court may, in its discretion, at any stage, allow the person, by whom such fee is payable, to pay the whole or part, as the case may be, of such court-fee; and upon such payment the document, in respect of which fee is payable, shall have the same force and effect as if such fee had been paid in the first instance.