ee. Legal Consequences
(1) Duty to Give Notice
Art. 79(4) requires the party that seeks exemption under Art. 79 to inform the other party of the impediment and its consequences:
(4) The party who fails to perform must give notice to the other party of the impediment and its effect on his ability to perform. If the notice is not received by the other party within a reasonable time after the party who fails to perform knew or ought to have known of the impediment, he is liable for damages resulting from such non-receipt.
Deviating from the general rule of Art. 27, the provision expressly requires that the notice actually reaches the promisee within a reasonable time. Failure to give notice in accordance with this provision results in a separate liability for damages the promisee incurred as result of this failure.
(2) Encompassed Remedies
Art. 79(5) is quickly overlooked. Yet, it is of paramount importance for a correct application of Art. 79:
(5) Nothing in this article prevents either party from exercising any right other than to claim damages under this Convention.
The provision is rather explicit about exemption under Art. 79 being limited to the promisee’s claim for damages. Other remedies of the promisee remain available. That also includes a claim for interest under Art. 78 which sometimes is mistaken for a claim for damages.
Since the promisee’s claim for specific performance is not encompassed by the wording of Art. 79(5) the question arises how the Convention treats this remedy in case of an impediment that renders specific performance objectively impossible. The outcome is quite clearly that a party cannot be legally compelled to fulfil a factually impossible duty, e.g. to deliver the specific goods that have been destroyed. Yet, the dogmatic explanation for this result is in dispute. Some authors resort to domestic law via Art. 28 while the prevailing view seems to resolve the issue by deducing a corresponding general principle from the rules on the passing of risk and Art. 79.