Termination of Contract in UK Law

So perhaps it would be simpler to say at the outset that frustration occurs whenever the law recognises that without default of either party a contractual obligation has become incapable of being performed because the circumstances in which performance is called for would render it a thing radically different from that which was undertaken by the contract.

Repudiation is a drastic conclusion which should only be held to arise in clear cases of a refusal, in a matter going to the root of the contract, to perform contractual obligations.

If one party so acts or so expresses himself, as to show that he does not mean to accept and discharge the obligations of a contract any further, the other party has an option as to the attitude he may take up. But repudiation by one party standing alone does not terminate the contract: it takes two to end it, by repudiation, on the one side, and acceptance of the repudiation, on the other.

The fact that a particular construction leads to a very unreasonable result must be a relevant consideration. The more unreasonable the result the more unlikely it is that the parties can have intended it, and if they do intend it the more necessary it is that they shall make that intention abundantly clear.

The test whether an event has this effect or not has been stated in a number of metaphors all of which I think amount to. the same thing; Does the occurrence of the event deprive the party who has further undertakings still to perform of substantially the whole benefit which it was the intention of the parties as expressed in the contract that he should obtain as the consideration for performing those undertakings?

(2) An act of acceptance of a repudiation requires no particular form: a communication does not have to be couched in the language of acceptance. It is sufficient that the communication or conduct clearly and unequivocally conveys to the repudiating party that that aggrieved party is treating the contract as at an end.

I. Frustration of a contract takes place when there supervenes an event (without default of either party and for which the contract makes no sufficient provision) which so significantly changes the nature (not merely the expense or onerousness) of the outstanding contractual rights and /or obligations from what the parties could reasonably have contemplated at the time of its execution that it would be unjust to hold them to the literal sense of its stipulations in the new circumstances; in such case the law declares both parties to be discharged from further performance.