1. A counterclaim or a claim for the purpose of a set-off shall be made no later than in the statement of defence provided that the arbitral tribunal has jurisdiction over it.

2. The respondent may not make a counterclaim or rely on a claim for the purpose of a set-off at a later stage in the arbitral proceedings, unless the arbitral tribunal considers it appropriate to allow such claim having regard to the delay in making it or prejudice to other parties or any other circumstances.