Sorry I'm not well versed in many ICAO documents, but in for US controllers it's found in the 7110.65. 5-7-1
http://www.faa.gov/air_traffic/publi...c/atc0507.html
d. Approach clearances cancel any previously assigned speed adjustment. Pilots are expected to make their own speed adjustments to complete the approach unless the adjustments are restated.
and also the AIM for pilots 4-4-12
http://www.faa.gov/air_traffic/publi...aim0404.html.7
f. If ATC determines (before an approach clearance is issued) that it is no longer necessary to apply speed adjustment procedures, they will inform the pilot to resume normal speed. Approach
clearances supersede any prior speed adjustment assignments, and pilots are expected to make their own speed adjustments, as necessary, to complete the approach. Under certain circumstances, however, it may be necessary for ATC to issue further speed adjustments after approach clearance is issued to maintain separation between successive arrivals. Under such circumstances, previously issued speed adjustments will be restated if that speed is to be maintained or additional speed adjustments are requested.