There may be factual situations which can at the same time be considered as cases of hardship and of force majeure. If this is the case, it is for the party affected by these events to decide which remedy to pursue. If it invokes force majeure, it is with a view to its non-performance being excused. If, on the other hand, a party invokes hardship, this is in the first instance for the purpose of renegotiating the terms of the contract so as to allow the contract to be kept alive although on revised terms.
General rule in RS §261, and three common specific instances of impracticability are dealt with in §§262, 263, and 264
Obligor may claim that some circumstance has so destroyed the value to him of the other party’s performance as to frustrate his own purpose in making the contract §265
Obligor may claim that he will not receive the agreed exchange for his own performance bc some circumstance has discharged the obligee’s duty to render that agreed exchange, on the ground of either impracticability or frustration. §§237 and 238