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1. Where a Contracting State has agreed in writing to submit to arbitration a dispute which has arisen or may arise out of a civil or commercial matter, that State may not claim immunity from the jurisdiction of a court of another Contracting State on the territory or according to the law of which the arbitration has taken or will take place in respect of any proceedings relating to:
(a) the validity or interpretation of the arbitration agreement;
(b) the arbitration procedure;
(c) the setting aside of the award,
unless the arbitration agreement otherwise provides.
2. Paragraph 1 shall not apply to an arbitration agreement between States.