Section 45 of the Principal Act is hereby amended -

(a) in subsection (1) by the insertion in paragraph (a) after "public roads" of "(other than motorways)", and

(b) in subsection (2) by the substitution for paragraphs (a) and (b) of the following:

"(a) a public road which is in a county or other borough, an urban district or a town, other than a road which is declared by the council of a county or the corporation of a county borough in bye-laws under section 46 of this Act not to be a public road in a built-up area for those purposes;

(b) a public road which is not in a county or other borough, an urban district or a town and which is declared by the council of a county in bye-laws under section 46 of this Act to be a public road in a built-up area for those purposes.".