Wiener Übereinkommen über das Recht der Verträge
Under Article 53 of the Vienna Convention on the Law of Treaties, any treaty that conflicts with a peremptory norm is void. The treaty allows for the emergence of new peremptory norms, but does not specify any peremptory norms. It does mention the prohibition on the threat of use of force and on the use of coercion to conclude an agreement: