as respects F1any part of England, the persons whose names are included in any pharmaceutical list are not such as to secure the adequate provision of pharmaceutical services in that F2... part, or

for any other reason any considerable number of persons in F3any part of England are not receiving satisfactory services under the arrangements in force under this Chapter.

may authorise F4NHS England to make such other arrangements as he may approve, or may himself make such other arrangements, and

may dispense with any of the requirements of regulations made under this Part (other than Chapters 2 to 4) so far as appears to him necessary to meet exceptional circumstances and enable such arrangements to be made.