Subject to the following provisions of this section and sections 17 and 18, the local planning authority may by resolution adopt the unitary development plan, either as originally prepared or as modified so as to take account of—
A unitary development plan shall not be adopted unless Part II of the plan is in general conformity with Part I.
A unitary development plan shall not be adopted by a London borough council unless Parts I and II of the plan are in general conformity with the spatial development strategy.
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Subject to the following provisions of this Chapter and to section 287, a unitary development plan for an area in England shall become operative on the date on which it is adopted.