24. Prohibition against vehicles overtaking at crossings
(1) Whilst any motor vehicle (in this regulation called 'the approaching vehicle') or any part of it is within the limits of a controlled area and is proceeding towards the crossing, the driver of the vehicle shall not cause it or any part of it :-
(a) to pass ahead of the foremost part of any other motor vehicle proceeding in the same direction; or
(b) to pass ahead of the foremost part of a vehicle which is stationary for the purpose of complying with regulation 23, 25 or 26.
(2) In paragraph (1) :-
(a) the reference to a motor vehicle in sub-paragraph (a) is, in a case where more than one motor vehicle is proceeding in the same direction as the approaching vehicle in a controlled area, a reference to the motor vehicle nearest to the crossing; and
(b) the reference to a stationary vehicle is, in a case where more than one vehicle is stationary in a controlled area for the purpose of complying with regulation 23, 25 or 26, a reference to the stationary vehicle nearest the crossing.