(1)F465For the purpose of securing that adequate guidance is given to drivers of motor vehicles as to whether any, and if so what, limit of speed is to be observed on any road, it shall be the duty of the [F462national authorityF462] , [F463in the case of a road for which [F464 the national authorityF464] is the traffic authority, toF463] erect and maintain . . . traffic signs in such positions as may be requisite for that purpose.
(2)[F466 In the case of any other road, it is the duty of the F467... traffic authority—F466]
(a)F465to erect and maintain . . . traffic signs in such positions as may be requisite in order to give effect to general or other directions given by the [F468national authorityF468] for the purpose mentioned in subsection (1) above, and
(b)to alter or remove traffic signs as may be requisite in order to give effect to such directions, either in consequence of the making of an order by the [F468national authorityF468] or otherwise.
(3)F471,F472If a F467[F469... traffic authorityF469] makes default in executing any works required for the performance of the duty imposed on them by subsection (2) above, the [F470national authorityF470] may ... execute the works; and the expense incurred ... in doing so shall be recoverable by [F473the national authorityF473] from the F467[F469... traffic authorityF469] and, in England or Wales, shall be so recoverable summarily as a civil debt.
[F474 (3A)In England, where subsection (3) applies in respect of non-compliance with a direction by a traffic authority other than a strategic highways company—
(a)a strategic highways company may execute the work required by the direction with the consent of the Secretary of State, and
(b)the expense incurred by the company in doing so is recoverable by the company from the authority summarily as a civil debt.F474]
(4)[F475 Where no such system of street or carriageway lighting as is mentioned in section 82(1) is provided on a road,F475] but a limit of speed is to be observed on the road, a person shall not be convicted of driving a motor vehicle on the road at a speed exceeding the limit unless the limit is indicated by means of such traffic signs as are mentioned in subsection (1) or subsection (2) above.
(5)In any proceedings for a contravention of section 81 of this Act, where the proceedings relate to driving on a road provided with [F476such a system of street or carriageway lightingF476] , evidence of the absence of traffic signs displayed in pursuance of this section to indicate that the road is not a restricted road for the purposes of that section shall be evidence that the road is a restricted road for those purposes.
[F477 (5A)In any proceedings for a contravention of section 81 of this Act, a certificate of an officer of the [F478 national authorityF478] F479 ... that a road is of a specified classification or type shall be sufficient evidence of the facts certified; and a document purporting to be such a certificate and to be signed by such an officer shall be deemed to be such a certificate unless the contrary is shown.F477]
(6)Where by regulations made under section 17(2) of this Act a limit of speed is to be observed, then, if it is to be observed—
(a)on all special roads, or
(b)on all special roads provided for the use of particular classes of traffic, or
(c)on all special roads other than special roads of such description as may be specified in the regulations, or
(d)as mentioned in paragraph (a), (b) or (c) above except for such lengths of special road as may be so specified,
this section shall not apply in relation to that limit (but without prejudice to its application in relation to any lower limit of maximum speed or, as the case may be, any higher limit of minimum speed, required by any such regulations to be observed on any specified length of any specified special road).
(7)The power [F480of the Secretary of StateF480] to give general directions under subsection (2) above shall be exercisable by statutory instrument.
[F481 (7A)The power of the Welsh Ministers to give general directions under subsection (2) is exercisable by statutory instrument.F481]
[F482 (8)The power of the Scottish Ministers to give general directions under subsection (2) is to be exercisable by Scottish statutory instrument.
(9)Before giving any general directions under subsection (2) the Secretary of State must consult with [F483 the Welsh Ministers andF483] the Scottish Ministers.
(10)Before [F484 the Welsh Ministers or the Scottish Ministers give any general directions under subsection (2) theyF484] must consult with the Secretary of State.F482]