25G. Procedure for retrenchment.- Where any workman in an industrial establishment, who is a citizen of India, is to be retrenched and he belongs to a particular category of workmen in that establishment, in the absence of any agreement between the employer and the workman in this behalf, the employer shall ordinarily retrench the workman who was the last person to be employed in that category, unless for reasons to be recorded the employer retrenches any other workman.