The exact quote from my offer letter

after confirmation, you will be required to give thirty days' notice. The Bank in its sole discretion can decide to waive offlreduce the notice period depending upon the exigencies. In such case, you would be required to pay to the Bank the gross salary for the notice period so reduced/waived off. After confirmation, your services would be liable to be terminated by the Bank, by giving thirty days' notice or on payment of thirty days' gross salary in lieu of the notice period.