JUDGMENT Mookherjee, J. 1. This appeal is directed against the judgment and order of a learned Single Judge, dated 8th April, 1993, on an application for writ, moved on behalf of the appellant/petitioner, inter alia, challenging a memorandum/letter, issued on behalf of the respondent by its General Manager (Personnel), dated 8th January, 1992, conveying the refusal of the Bank to accept the appellant's prayer for permitting him to voluntarily retire from service of the Bank, effective from 1st February, 1992, and also the proposed initiation of a disciplinary proceeding against him for the irregularities allegedly committed by him. The learned Single Judge, by his order under appeal, in substance, refused to hold that there was any irregularity and illegality in issuance of the said letter by the respondent Bank and rejected the writ application. 2. Admittedly, the appellant had been holding a very high position as an officer of the Bank, and had been posted from time to time at different places and even abroad. One such posting of the appellant had been as Chief Executive of U.K. operations, to wit, as General Manager of the London Branch of the Bank. During the period of his posting in London, which spread over a period of more than three years (16.6.1988 to 29.11.1991), his promotion as General Manager, took place on or about 17.11.1990, with effect from 16.4.1990. By letters of the Bank, dated 30th August, 1991 and 14th November, 1991, the appellant had been asked on behalf of the Bank, to hand over charge to one Sri Ahuja and in compliance with the same the appellant handed over charge to Sri Ahuja on 24.11.91. By a letter, dated 18th December, 1991, the appellant communicated to the Bank that he decided to take voluntary retirement with effect from 1st February, 1992, and, with that end in view, landed at Delhi on 14th December, 1991. The appellant in that letter further informed the Bank that a formal letter seeking voluntary retirement was being sent separately. A formal letter from the appellant, as informed, dated 20th December, 1991, followed, inter alia, with a request to waive the three months' notice period. During pendency of the writ proceeding before this Court, in terms of an order dated 25th of February, 1992 granting liberty to the Bank. Articles of charge, dated 29th February, 1992, had been served on the appellant. 3. During pendency of the writ proceeding before this Court, in terms of an order dated 25th of February, 1992 granting liberty to the Bank. Articles of charge, dated 29th February, 1992, had been served on the appellant. 3. The articles of charge purported to embody certain alleged derelictions of duties and abuse of power by the appellant as an officer of the Bank, not only during his stay in India but also during his posting abroad. The relevant period was between May 1985 to November 1991. The presumed condonation of defaults or acts of delinquencies up to 17.11.1990, when the appellant was promoted as General Manager, has been attempted to be negatived or countered on the basis of the stand, taken by the respondents, in their affidavit-in-opposition, to be specific, in Paragraph 15 thereof, to the effect that the promotion in question had been granted before the serious breaches and/or irregularities committed by the appellant came to light. Apart from that the respondents emphasised that some of the charges pertained to a period posterior to the date of promotion, and, therefore, the same could not be said to have been erased by promotion. 4. Both the contesting parties, the appellant being represented by Mr. Maloy Kumar Basu, learned Senior Advocate, and the respondents by Mr. B.P. Gupta, another learned Senior Advocate, made submissions, hinging on the constructions of Regulations 19 and 20 of the UCO Bank (Officers) Service Regulations, including their applicability and effect, in the factual backdrop, as recorded above. In the present case, Regulation 19, which is the Regulation relating to the age of retirement, by proviso to sub-regulation (2) thereof, vests a right in an officer/employee for retiring earlier, at his option, in accordance with the rules of the Bank. Regulation 20, on the other hand relates to termination of service and by sub-regulation (2) thereof, a prohibition has been imposed on an officer from leaving or discontinuing his service in the Bank or resigning therefrom without giving a notice in writing for three months, by Clause (a) of sub-regulation (3), in case of pendency of a disciplinary proceeding against an officer, he cannot leave, discontinue or resign from service without prior approval in writing of the competent authority and any notice of resignation given by such officer, before or during the disciplinary proceeding cannot take effect unless it is accepted by the competent authority. By clause (b) of the said sub-regulation, it has been laid down that placement of an officer under suspension or issuance of a notice to showcause as to why disciplinary proceeding shall not be instituted or submission of a charge-sheet would have the effect, as if, a disciplinary proceeding is pending and such pendency would be deemed till the final orders therein. 5. On a careful analysis of the submissions made by the respective Counsel, the first question which arises for consideration is whether in view of the promotion granted to the appellant on 17th November, 1990, the acts of delinquency on his part, which constitute the substratum of the articles of charge/the pending disciplinary proceeding, can be said to have been waived or erased. The decision of the Supreme Court in the case of (1) State of Punjab v. Dewan Chunilal reported in AIR 1970 SC 2086 , had been cited. The said case is distinguishable on facts inasmuch as the reports earlier than the date of promotion, did not constitute serious infirmities this was manifested by absence of any action on the part of the authorities, prejudicial to the respondent in that case and the fact that on the contrary the said authorities recommended the case of the Officer as one fit for crossing the efficiency bar. No plea was taken that such reports were not known to the authorities prior to the passing of order in favour of the respondent in the cited case. In the instant case, however, the articles of charge disclosed acts of delinquencies which have been emphatically claimed not to have become known to the authorities prior to the date of promotion granted to the appellant. The principle of waiver, which cannot have any application unless the right of the party, who is alleged to have waived, to act on such reports, can be said to have been within the knowledge of such party. There cannot be waiver of a right, which is not known. Reference may be made, in this connection, to the case of (2) M/s. Motilal Padampat Sugar Mills Company Limited v. The State of Uttar Pradesh and Ors. reported in AIR 1979 SC 621 . There cannot be waiver of a right, which is not known. Reference may be made, in this connection, to the case of (2) M/s. Motilal Padampat Sugar Mills Company Limited v. The State of Uttar Pradesh and Ors. reported in AIR 1979 SC 621 . The criteria laid down in that case, do not appear to have been fulfilled in the present case and as such the point must have to be answered against the appellant and in favour of the respondents. 6. The second question is whether Regulations 19 and 20 are independent of each other and operate in different fields or they are inter-dependent and one is controlled by the other. In case it is found that they are supplemental to each other, which of the two controls the other? In this connection, it is to be noted that both Regulations 19 and 20 embody provisions, inter alia, permitting the employee to retire or leave the services or resign from the Bank on giving three months notice unless such period of notice is either waived fully or partially by the competent authority. In the instant case, even if the applicability of Regulation 19 or Regulation 20 is kept open, there being admittedly, no waiver or reduction of period of notice, granted by the competent authority, the appellant's right to voluntarily retire or leave the services of the Bank or resign cannot be said to have accrued before 17th of March, 1992. There can be, therefore, no controversy that the disciplinary proceeding had commenced before the expiry of the said period of 3 months with the framing of the articles of charge, on 29th February, 1992, though with the leave of the Trial Court. 7. In the backdrop of the aforesaid factual and legal positions, we proceed to deal with the third question, which is, by nature, an off shoot of the second question, which we have already considered hereinabove. In this connection, we have to construe sub-regulation (2) of Regulation 20 of the Service Regulations. The said sub-regulation imposes a mandatory restraint on an Officer from leaving or discontinuing his service in the Bank (emphasis supplied). In this connection, we have to construe sub-regulation (2) of Regulation 20 of the Service Regulations. The said sub-regulation imposes a mandatory restraint on an Officer from leaving or discontinuing his service in the Bank (emphasis supplied). While trying to find out the meaning and expanse of the word "leave" or "discontinue service" and whether the said restriction applies to a case of voluntary retirement as contemplated by Regulation 19 or merely applies to the case of resignation by an Officer as contemplated by Regulation 20, it is pertinent to note that the said sub-regulation (2) does neither use the word "resignation" nor "retirement" the user of which could have been a clear pointer to the intended application of the said sub-regulation (2) to either of the two cases. It will, therefore, be not unjustified to presume that the sub-regulation (2) was not meant to be confined to "termination" or "resignation" as provided for by Regulation 20. The terms "leave" or "discontinue his service" should, therefore, be given its plain grammatical meaning, as laid down by the Supreme Court, in the case of (3) Superintendence Company of India v. Krishan Murgi reported in AIR 1980 SC page 1721, wherein it was held to connote voluntary action, synonimous with the expression "quit". In consequence, therefore, it follows that even in case of voluntary retirement in terms of Regulation 19 of the said Service Regulations, Clauses (a) and (b) of sub-regulation (3) would also be attracted and apply. In view of the factual position, as noted by us hereinabove, that the articles of charge had been served before the expiry of notice period of three months, a disciplinary proceeding could be said to be pending on the date the voluntary retirement was prayed to be effective. The appellant, therefore, squarely became liable to the dis-entitlement as envisaged in sub-regulation (2) of Regulation 20. He could not, therefore, lawfully claim relief in terms of Regulation 19. For the reasons aforesaid, the reliefs asked for by him in the writ cannot be allowed. The writ application was, therefore, rightly dismissed by the learned Trial Judge and judgment under appeal, in our view, does not call for any interference. The appeal, therefore, fails and is dismissed. There will, however, be no order as to costs. Khare, C. J.: I agree.