Answer ... In international commercial arbitration, the parties cannot validly restrict or eliminate the power of the arbitral tribunal to rule on an objection to its jurisdiction in a preliminary award or the final award. Therefore, before arbitration commences (ie, before a request for arbitration is received), any party can file a motion for the court to rule on the existence and validity of the arbitration agreement. To hear the case, a Greek court must have jurisdiction over the dispute.

Answer ... In domestic arbitration and international disputes of a non-commercial nature, the tribunal can rule on its own jurisdiction, unless the parties have agreed otherwise.

Answer ... Once a case has been filed and arbitration has commenced, no challenges to the tribunal’s jurisdiction before a court are allowed until the arbitral award has been rendered.