92. Subject to the provisions of this Constitution. the Supreme Court shall, to the exclusion of any other court have an original jurisdiction in any dispute between any two or more of the following parties, that is to say, the Federation and the units, if and in so far as the dispute involves any question (whether of law or fact) on which the existence or extent of a legal right depends:

Provided that the said jurisdiction shall not extend to a dispute to which an Indian State is a party if the dispute arises out of any provision of a treaty, agreement, engagement, sanad or other similar instrument which was entered into or executed before the commencement of this Constitution, or which expressly provides that the said jurisdiction shall not extend to such a dispute.