Arbitration clause with an express reservation regarding the enforcement of contractual obligations. Possibility of analysis of the enforcement of the security offered by the appellants by the judiciary. However, "the challenged decision could not have analyzed the question of the validity of the guarantee contract, but only the question of the contractual default pointed out by the appellees and the subjection of the appellants' credits to the court-supervised reorganisation proceedings". Questions pertaining to the regularity of the fiduciary security must be submitted to the arbitral tribunal: