9Any remuneration payable under the last foregoing paragraph and any other expenses of the tribunal shall be paid by the Minister out of money provided by Parliament, but any such expenses except so far as—
(a)they are met out of the payment of fees, and
(b)they may be apportioned by the tribunal to the exercise of the tribunal's jurisdiction under Part IV of the Road Traffic Act, 1960,
shall be repaid on demand to the Minister by the Commission or, after the vesting date, by the Railways Board and the London Board in such proportions as they may agree or as the Minister may in default of agreement determine.