CISG Article 73
1. In the case of a contract for delivery of goods by instalments, if the failure of one party to perform any of his obligations in respect of any instalment constitutes a fundamental breach of contract with respect to that instalment, the other party may declare the contract avoided with respect to that instalment.
2. If one party's failure to perform any of his obligations in respect of any instalment gives the other party good grounds to conclude that a fundamental breach of contract will occur with respect to future instalments, he may declare the contract avoided for the future, provided that he does so within a reasonable time.
3. A buyer who declares the contract avoided in respect of any delivery may, at the same time, declare it avoided in respect of deliveries already made or of future deliveries if, by reason of their interdependence, those deliveries could not be used for the purpose contemplated by the parties at the time of the conclusion of the contract.
ULIS Article 75
1. Where, in the case of contracts for delivery of goods by instalments, by reason of any failure by one party to perform any of his obligations under the contract in respect of any instalment, the other party has good reason to fear failure of performance in respect of future instalments, he may declare the contract avoided for the future, provided that he does so promptly.
2. The buyer may also, provided that he does so promptly, declare the contract avoided in respect of future deliveries or in respect of deliveries already made or both, if by reason of their interdependence such deliveries would be worthless to him.
"Article 75 ULIS lays down special rules for the instalment contract . . . but leaves disturbances to a defective instalment to be treated according to the general rules. In the event of a disturbance to one instalment, it gives a right to avoid the contract for the future if there is good reason to fear future disturbances. Moreover, if future deliveries would cease to have any interest for the buyer, he can declare all or part of the contract avoided. . . .
"Article 73 of the Convention does not provide supplementary remedies in order to deal with instalment contracts but lays down a comprehensive principle with applies to both parties. A disturbance to a present delivery was taken as the starting point in Article 73(1). A slight reformulation was made in order to achieve a greater degree of objectivity in cases where there was a risk of a breach in respect of future deliveries. Moreover, the right in Article 73(3) to declare the whole or part of the contract avoided ceased to depend on the worthlessness of the deliveries to the buyer (as in Article 75 ULIS) and was made subject to the more objective test of whether, by reason of their interdependence, the deliveries could not be used for the purpose contemplated by the parties. . . ." Leser in Commentary on the UN Convention on the International Sale of Goods, Peter Schlechtriem ed. (Oxford 1998) 542-543 [citations omitted].