27.— Section 153 (amended by section 45 of the Act of 2010) of the Act of 2000 is amended—

(a) by repealing subsection (6),

(b) by substituting the following subsections for subsection (7):

“(7) Where a planning authority establishes, following an investigation under this section that unauthorised development (other than development that is of a trivial or minor nature) has been or is being carried out and the person who has carried out or is carrying out the development has not proceeded to remedy the position, then the authority shall issue an enforcement notice under section 154 or make an application pursuant to section 160, or shall both issue such a notice and make such an application, unless there are compelling reasons for not doing so.

(8) Nothing in this section shall operate to prevent or shall be construed as preventing a planning authority, in relation to an unauthorised development which has been or is being carried out, from both issuing an enforcement notice under section 154 and making an application pursuant to section 160.”.