The rights and obligations of the Authority under this Contract shall not be assigned, novated or otherwise transferred (whether by virtue of any Legislation or any scheme pursuant to any Legislation or otherwise) to any person other than to any public body (being a single entity), [acquiring the whole of the Contract and] having the legal capacity, power and authority to become a party to and to perform the obligations of the Authority under this Contract being:
(a) a Minister of the Crown pursuant to an Order under the Ministers of the Crown Act 1975 or a Northern Ireland Department pursuant to an Order under the Ministries (Northern Ireland) Act 1944; or
(b) any other public body whose obligations under this Contract are unconditionally and irrevocably guaranteed (in a form reasonably acceptable to the Contractor) by the Authority or a Minister of the Crown having the legal capacity, power and authority to perform the obligations under the guarantee and the obligations of the Authority under this Contract.