S. R. NAYAK, J, J. ( 1 ) THIS writ petition is directed against the order passed by the a. P. Administrative Tribunal (for short "the tribunal") at Hyderabad, dated 2. 3. 1998 made in O. A. Nos. 25449 and 25450 of 1990 dismissing the original applications filed by the petitioners. ( 2 ) THE petitioners herein were applicants 1 and 2 respectively in the Original application Nos. 25449 and 25450/1990. The petitioners and another applicant by name Mr. J. A. Gafoor assailed the validity of the proceedings No. A5d/l 1432/88, dated 22. 3. 1990 issued by the Chief Accounts officer, Directorate of Medical and Health services, A. P. , Hyderabad whereby and whereunder the earlier order dated 27. 3. 1986 granting Selection Grade to the petitioners with effect from 10. 9. 1973 was revoked. ( 3 ) FEW facts relevant to the decision making be noted briefly as under: Petitioner no. 1 was appointed as Typist on 4. 1. 1966 and petitioner No. 2 was appointed as Typist on 8. 5. 1967. While the petitioners were serving as Typists, they opted for the post of l. D. Accounts (Junior Assistant) with effect from 1. 5. 1968. On an earlier occasion by the proceedings dated 27. 3. 1986, the respondent authorities taking into account the services rendered by the petitioners in the post of L. D. Accounts (Junior Assistant) had passed the order granting Selection grade to the petitioners with effect from 10. 9. 1973, the day on which their immediate junior one V. Mohan Rao was granted selection Grade. Subsequently, that order was revoked by the impugned order dated 22. 3. 1990 on the ground that the petitioners did not put in five years of qualifying service in the post of Typists in terms of Rule 46-A of the A. P. State and Subordinate Service rules, 1962 (for short "the Rules") and therefore, they are not entitled to Selection grade scale. ( 4 ) ASSAILING the Governmental Order dated 22. 3. 1990 as well as the order of the learned Tribunal, the learned Counsel for the petitioners would maintain that the order made by the respondent authorities on 22. 3. 1990 is not sustainable in view of the government Order in G. O. Ms. No. 190, dated 10. 6. 1983. ( 4 ) ASSAILING the Governmental Order dated 22. 3. 1990 as well as the order of the learned Tribunal, the learned Counsel for the petitioners would maintain that the order made by the respondent authorities on 22. 3. 1990 is not sustainable in view of the government Order in G. O. Ms. No. 190, dated 10. 6. 1983. On the other hand, learned government Pleader for Services-Hi would support the impugned order contending that admittedly the petitioners have not put in five years of qualifying service in the post of Typists and therefore they do not satisfy the conditions prescribed under Rule 46-A of the Rules to claim Selection Grade scale. ( 5 ) THE claim put forth by the petitioners is covered by the rules framed by the Governor under the proviso to Article 309 of the Constitution. Rule 46-A deals with selection grades and revised pay scales to be attached to such grades. Sub-rule 4 (a) of rule 46-A among other things prescribes that no person shall be appointed to a post borne on the Selection Grade of any class or category unless he is an approved probationer in that class or category and has put in a minimum service of not less than five years in that class or category. Thus, in order to claim selection grade, one should satisfy two conditions in terms of clause (a) of sub-rule (4) of Rule 46-A. The first condition is that he should be an approved probationer in the class in which he claims the selection grade. The second condition is that he should have put in minimum service of five years in that class or category of service. It cannot be gainsaid that the petitioners herein made entry into the service as Typists. If they were to seek selection grade on that basis, the clear mandate of the rule over which there cannot be any controversy or confusion is that they should have put in minimum qualifying service of five years in that post. This is a condition precedent to claim selection grade. Admittedly, the petitioners did not put in five years of qualifying service in the post of Typist. ( 6 ) PARAGRAPH-3 of the G. O. Ms. No. 190, dated 10. 6. This is a condition precedent to claim selection grade. Admittedly, the petitioners did not put in five years of qualifying service in the post of Typist. ( 6 ) PARAGRAPH-3 of the G. O. Ms. No. 190, dated 10. 6. 1983 reads:"in the Government Memo fourth read above it was ordered that an officer who is out of his regular line may be allowed to draw pay of the Selection Grade posts which he would have otherwise received had he remained in his regular line. The benefit was however, restricted on the principle of "one for one" i. e. , the senior most among the persons in this category absent from the regular line was entitled to get the benefit against one junior, appointed to Selection Grade in the regular line. " ( 7 ) IT is true that in terms of paragraph-3, an Officer who is out of his regular line of service like the petitioners may be allowed to draw pay of the Selection Grade post, which he would have otherwise received had he remained in his regular line. However, this concession shown in the Government order in favour of the employees who are out of regular line of service is not unconditional, as could be seen from paragraph-3 itself. Be that as it may, we are afraid we could possibly enforce the directive contained in para-3 of the Government Order which according to us is in conflict with sub-rule (4) of Rule 46-A of the Rules. When the statutory rule in an unmistakable language clearly mandates that unless an official puts in a minimum of five years of service in the concerned class or category of service, he is not entitled to Selection Grade, it is not permissible for the Government to issue administrative instructions which have the effect of causing violence to clear intendment of the statutory rule. ( 8 ) THE Government can only supplement the statutory rule and cannot supplant it in exercise of its executive power. In that view of the matter, no exception can be taken to the impugned Government Order dated 22. 3. 1990 or to the order of the learned tribunal impugned in this writ petition affirming the action of the Government. ( 9 ) IN the result, the writ petition is dismissed. No costs.