70.9 Designer Collateral Warranty
To the extent that any Designer is engaged after the Contract Date:
(a) the Service Provider shall, unless otherwise required by the Authority, use reasonable endeavours to procure that on entering into a sub-contract, the Designer enters into a collateral warranty with the Authority;
(b) any collateral warranty from the Designer shall impose no greater obligations upon the Designer than are imposed on it under the sub-contract entered into;
(c) the Service Provider shall obtain the prior written approval of the Authority to the terms of the sub-contract prior to the commencement of the obligations of the Designer, such approval not to be unreasonably withheld or delayed.