Judgment :- 1. These two appeals arise from the common order of the learned Subordinate Judge, Kottayam in O. P. (Arb.) Nos. 33 of 1984 and 85 of 1984 revoking the authority of the arbitrator to be appointed in terms of the arbitration clause contained in the contract in writing between the parties. This order is made on the basis of applications filed by the respondent (the "contractor") in each of these appeals under S.20 of the Arbitration Act, 1940. 2. The contention of the contractor was that amounts were due and payable to him by the appellants (the "company") in respect of work executed by him in accordance with Ext. B1 agreement. The company stated that there was no arbitrable dispute between the parties as the contract was fully performed and the contractor's claims thereunder had been finally settled. The contractor in either proceeding contended that he was entitled to certain extra payment on account of escalation in price. The reply of the company was that no such extra payment was due or payable once the final bill was paid and the amount was accepted by the contractor in full settlement of all his claims. The learned judge revoked the jurisdiction of the arbitrator, who was yet to be appointed by the designated officer in accordance with the terms of the contract, and allowed the contractor to nominate his own arbitrator. We are surprised that the learned judge passed no order in either proceeding under S 20(4). He should have disposed of the application either by ordering or not ordering the filing of the arbitration agreement. If he had ordered that the agreement be filed, it was then for the designated authority mentioned under the agreement to appoint the arbitrator. Only if such authority refused to do so, was it open to the court to appoint an arbitrator. 3. The facts in M.F.A. No. 129 of 1986 are: Pursuant to Ext. BI, the contractor commenced execution of the work, He was expected to complete the work on or before 25-3-1979. But by mutual agreement time was extended upto 10-1-1981. The work was completed by him by that time. The final bill signed by both the parties was prepared on 3-7-1982. The entire amount due to the contractor, as per the final bill was paid. But by mutual agreement time was extended upto 10-1-1981. The work was completed by him by that time. The final bill signed by both the parties was prepared on 3-7-1982. The entire amount due to the contractor, as per the final bill was paid. Subsequently the contractor by his letter dated 22-9-1982 asked the company for additional amounts by way of extra rates for the work already done and paid for in terms of Ext. B3. This additional payment was sought allegedly on the ground that the prices had escalated. This claim was refuted by the company by Ext. B5 dated 8-12-1982. The contractor then called upon the company by Ext. B6 dated 22-12-1982 to appoint an arbitrator in terms of the agreement. The company stated by Ext. B7 dated 14-4-1983 that there was no arbitrable dispute as all claims of the contractor under the contract had been fully and finally settled. Thereupon the contractor moved the court below under S.20. 4. The facts in M.F.A. No. 130 of 1986 are identical except in one respect. Like in M.F.A. No. 129 of 1986, so in M.F.A. No. 130 of 1986, work was completed; final bill was submitted and paid; subsequently the contractor claimed additional rates allegedly on the ground of escalation of prices; that was refuted by the company; thereupon he demanded that an arbitrator be appointed; the company stated that there was no arbitrable dispute, and, the contractor then moved the court under S.20. But one crucial difference between the two cases is that in M.F.A. 130 of 1986 Ext. B5 dated 23-5-1983 addressed by the contractor to the company evidences full and final settlement. This letter states: "Final bill at the above work recorded from page 62 to 95 of M. Book No. 1902 has been accepted and certified that there are no further claims as far as this work is concerned. (emphasis supplied) There is no dispute that the claim in question concerns the work mentioned in Ext. B5. It records the full and final settlement of all claims in relation to that work. In the circumstances, in so far as M.F.A. No. 130 of 1986 is concerned, the contractor has in writing recorded his full satisfaction. No such clear evidence exists in writing in M.FA. No. 129 of 1986. B5. It records the full and final settlement of all claims in relation to that work. In the circumstances, in so far as M.F.A. No. 130 of 1986 is concerned, the contractor has in writing recorded his full satisfaction. No such clear evidence exists in writing in M.FA. No. 129 of 1986. This is the crucial difference between the two cases on which the question of law discussed at the bar turns. 5. It is well settled that unilateral repudiation or rescission of the contract does not put an end to the operation of the arbitration clause. The object of this clause, which is supplementary and collateral in character, is settlement of disputes arising under the contract. If the contract is brought to an end by the unilateral action of one of the parties, the claims which arose under the contract are not automatically destroyed. All disputes respecting such claims, whether they relate to performance during the period prior to the repudiation or to damages consequent upon repudiation, remain arbitrable under the contract and the jurisdiction of the arbitrator remains in full force. On the other hand, if the contract never existed or it was void ab initio; or if the parties have by mutual agreement put an end to the contract by superseding it by another contract; or if they have mutually acknowledged due and complete performance of the contract, then nothing further remains to be done under the substantive terms of the contract, and the collateral agreement contained in the arbitration clause does not survive the contract. This is the principle adopted by the Supreme Court in Union of India v. Kishorilal, AIR 1959 SC 1362. This is the principle adopted by the Supreme Court in Union of India v. Kishorilal, AIR 1959 SC 1362. Subba Rao, J., speaking for the majority, observed: "The following principles relevant to the present case emerge from the aforesaid discussion: (1) An arbitration clause is a collateral term of a contract as distinguished from its substantive terms; but none the, less it is an integral part of it; (2) however comprehensive the terms of an arbitration clause may be, the existence of the contract is a necessary condition for its operation, it perishes with the contract; (3) the contract may be non est in the sense that it never came legally into existence or it was void ab initio; (4) though the contract was validly executed, the parties may put an end to it as if it had never excised, and substitute a new contract for it solely governing their rights and liabilities thereunder; (5) in the former case, if the original contract has no legal existence, the arbitration clause also cannot operate, for along with the original contract, it is also void; in the latter case, as the original contract is extinguished by the substituted one the arbitration clause of the original contract perishes with it; and (6) between the two fall many categories of disputes in connection with a contract, such as the question of repudiation, frustration, breach etc. In these cases it is the performance of the contract that has come to an end. but the contract is still in existence for certain purposes in respect of disputes arising under it or in connection with it. As the contract subsists for certain purposes, the arbitration clause operates in respect of these purposes." See Damodar Valley v. K. K. Kar, AIR 1974 SC 158; Malhati Jute Mills v. Khyalirsa, AIR 1968 SC 522; Paul Wilson & Co. v. Blumenthal, (1983) 1 All. ER 34; Heyman v. Darwins Ltd., (1942) AC 356 (H.L.): (1942) 1 All ER 337 (H. L.), Hirji Mulji v. Cheong Yue Steamship Co. (1926) A.C.497 (PC). See also the judgment in M.F.A. Nos. 115 & 116 of 1985. 6. The argument of the company is that the arbitration clause ceased to operate when the contract was duly and completely performed. (1926) A.C.497 (PC). See also the judgment in M.F.A. Nos. 115 & 116 of 1985. 6. The argument of the company is that the arbitration clause ceased to operate when the contract was duly and completely performed. Shri. M. Ramachandran, appearing for the company, submits that the dispute sought to be raised is not one arising under or in respect of or relating to the contract. The dispute is as to the very existence of the contract. Where the parties have by mutual consent recorded satisfaction of all claims which arose under the contract, and full and final payment has been made and accepted, nothing remains to be done under the contract, and the contract has therefore ceased to exist. In such circumstances, counsel points out, the arbitration clause, though collateral and supplementary, but being an integral part of the contract, has no separate life of its own. This argument is perfectly valid provided the facts support it. 7. In M.F.A.No.129 of 1986 there is no clinching evidence that the parties came to a full and final settlement. We say this notwithstanding Ext. B3 which is the final bill signed by both parties. No document has been produced to show that the cheque paid under that bill was accepted by the contractor in full and final settlement. On the other hand, there is such a document in M.F.A.No.130 of 1986, that is Ext. B5 dated 23-5-1983 which we have set out above. That is a case which squarely falls within the principle relied on by Shri. Ramachandran. Nothing survives in that case. The arbitrator has no jurisdiction. The court has no power to appoint one. M.F. A. No. 130 of 1986 is accordingly allowed, and the order under appeal is set aside. The suit shall stand dismissed. 8. Since the full and final settlement in M.F.A. No. 129 of 1986 is not in evidence-at any rate not in clear evidence-we are of the view that the question as to full and final settlement is itself a matter which has to be decided by the arbitrator. Unlike in the other case where the question cannot arise because of the clear and categoric admission of the contractor in writing, here the question is still at large and is therefore arbitrable along with the other questions raised by the contractor. 9. Unlike in the other case where the question cannot arise because of the clear and categoric admission of the contractor in writing, here the question is still at large and is therefore arbitrable along with the other questions raised by the contractor. 9. However, as already stated, the court below did not pass a proper order under S.20. The court ought to have, in the light of the reasoning which it adopted, directed the filing of the arbitration agreement and thereupon the designated authority should have been given time to appoint an arbitrator. Only if that authority refused to comply, or failed to comply within reasonable time, with the direction in that behalf, could the court exercise its power to appoint an arbitrator. That is what it ought to have done. However, there is no need to send back the case for that purpose to the court below. Accordingly we order that the appellant shall file the arbitration agreement in the court below. Shri. Ramachandran submits that the arbitration agreement will be filed in the court below forthwith, and within a month from today the designated officer will appoint the arbitrator in terms of the agreement. This submission is recorded. In the circumstances, M.F.A No. 129 of 1986 is allowed to the limited extent indicated above, and to that extent the order under appeal shall stand set aside. 10. The appellant is entitled to costs throughout in both the appeals.