http://www.legislation.gov.uk/uksi/2005/476/schedule/paragraph/73/made

The Traffic Management (Strategic Roads in Greater London) Designation Order 2005

Roads and highways

King's Printer of Acts of Parliament

2017-06-20

HIGHWAYS, ENGLAND

Section 60 of the Traffic Management Act 2004 enables the Secretary of State to designate roads and proposed roads in Greater London, other than roads for which the Secretary of State or Transport for London is the traffic authority, as strategic roads for the purposes specified in that section; namely the purposes of section 301A of the Highways Act 1980 and section 121B of the Road Traffic Regulation Act 1984 (each of which imposes restrictions on the exercise by London borough councils of powers under the relevant Act so as to affect a GLA road, a strategic road or a road in another London borough other than a GLA road or strategic road). The designated roads are specified in the Schedule and they will become strategic roads with effect from 5th September 2005.