Clausula rebus sic stantibus is the legal doctrine allowing for a contract or a treaty to become inapplicable because of a fundamental change of circumstances. In public international law the doctrine essentially serves an "escape clause" to the general rule of pacta sunt servanda (promises must be kept).[1]: 28 Because the doctrine is a risk to the security of treaties, as its scope is relatively unconfined, the conditions in which it may be invoked must be carefully noted.[1]: 23–28 [2]
This term is related to force majeure and hardship clause.