۱. Before taking countermeasures, an injured State shall:
(a) call upon the responsible State, in accordance with article ۴۳, to fulfil its obligations under part two;
(b) notify the responsible State of any decision to take countermeasures and offer to negotiate with that State.
۲. Notwithstanding paragraph ۱ ( b), the injured State may take such urgent countermeasures as are necessary to preserve its rights.
۳. Countermeasures may not be taken, and if already taken must be suspended without undue delay if:
(a) the internationally wrongful act has ceased; and
(b) the dispute is pending before a court or tribunal which has the authority to make decisions binding on the parties.
۴. Paragraph ۳ does not apply if the responsible State fails to implement the dispute settlement procedures in good faith.