4.—(1) Subject to sub-paragraphs (2) and (3), if as the result of the authorised development or their construction, or of any subsidence resulting from any of those works any damage is caused to any electronic communications apparatus belonging to an operator (other than apparatus the repair of which is not reasonably necessary in view of its intended removal for the purposes of those works, or other property of an operator) the undertaker must bear and pay the cost reasonably and properly incurred by the operator in making good such damage.
(2) Nothing in sub-paragraph (1) is to impose any liability on the undertaker with respect to any damage to the extent that it is attributable to the act, neglect or default of an operator, its officers, servants, contractors or agents.
(3) Any difference arising between the undertaker and the operator under this paragraph is to be referred to and settled by arbitration under article 34 (arbitration).