USA/USSR Joint Statement on Uniform Acceptance of Rules of International Law Governing Innocent Passage

The Joint Statement by the USA and the USSR (the superpowers of the time) was made to counteract state activity to restrict the passage of ships carrying potentially hazardous materials through states' territorial sea, culminating mainly from the Basel Convention 1989. It was made on 23 September 1989.
It made it clear that the text of the 1982 United Nations Convention on the Law of the Sea (UNCLOS) reflected customary international law, and every ship, regardless of cargo, does not need permission to enter another state's territorial sea so long as it adheres to the definition of innocent passage in Article 19 of UNCLOS.