After section 60 insert -

"60A Certain principles etc to be considered or applied from IP completion day

(1) This section applies when one of the following persons determines a question arising under this Part in relation to competition within the United Kingdom -

(a) a court or tribunal;

(b) the CMA;

(c) a person acting on behalf of the CMA in connection with a matter arising under this Part.

(2) The person must act (so far as is compatible with the provisions of this Part) with a view to securing that there is no inconsistency between -

(a) the principles that it applies, and the decision that it reaches, in determining the question, and

(b) the principles laid down by the Treaty on the Functioning of the European Union and the European Court before IP completion day, and any relevant decision made by that Court before IP completion day, so far as applicable immediately before IP completion day in determining any corresponding question arising in EU law,

subject to subsections (4) to (7).

(3) The person must, in addition, have regard to any relevant decision or statement of the European Commission made before IP completion day and not withdrawn.