Dear friend,
If the contract of employment stipulates a particular length of notice period or payment in lieu thereof on unilateral termination on either side, whether the employer or the employee, whoever resorts to such unilateral termination, should honor it by means of any one of the alternatives mentioned therein. Of course, the employer has got a managerial prerogative based on exigencies of work to turn down the offer of payment in lieu of notice by a resigning employee. However, when the employee's resignation is effective from a future date and he is willing to serve the entire notice period, in case the employer insists on immediate relief, it amounts to a counter offer by the employer himself and therefore he is legally bound to pay the notice salary already stipulated.