I looked up a couple of utilities, and their limit of approach for that voltage is 4.0-4.5 m or 13-15'. So this vegetation is already within the limit, so unless you are a Certified Utility Arborist (or equivalent), you cannot cut that brush.
I don't work within LOA, but I know our CUA has a dedicated pole pruner that is tested for use only when he is in the LOA.