1. Explicit Repudiation: A state may explicitly repudiate a treaty by formally declaring its intention not to be bound by it anymore. This can be done through a statement, note, or announcement by the government.
2. Material Breach: A state can violate a treaty by failing to fulfill its obligations or by committing acts that significantly undermine the purpose or object of the treaty. Such material breaches can include actions like non-compliance, non-performance, or hindrance of treaty provisions.
3. Non-Performance: A state may simply fail to perform its obligations under the treaty without explicitly repudiating it. This non-performance can be intentional or due to inability or unwillingness to comply.
4. Fundamental Change of Circumstances: If there has been a fundamental change of circumstances that has radically transformed the context of the treaty, a state may argue that it is no longer bound by the treaty. However, this principle is narrowly applied and subject to strict conditions.
5. Subsequent Treaties or Agreements: A later treaty or agreement between the same parties may supersede or modify an earlier treaty. This is known as the principle of "lex posterior derogat priori" (the latter law overrides the former).
6. Conflict with Jus Cogens: Treaties that conflict with peremptory norms of international law, known as jus cogens, may be considered invalid and therefore not binding on states.
7. Impossibility of Performance: If the performance of a treaty becomes impossible due to factors beyond a state's control, it may be relieved of its obligations under the treaty.
It's important to note that the interpretation and application of treaty violations can be complex and often involve disputes between the parties involved. The consequences and remedies for treaty breaches also depend on the specific provisions and mechanisms outlined in the treaty itself and in international law.