Just looked this up on the Web and found 2 slightly differing versions:
Version 1:
In Class A,B,D airspace (or Class F above FL100) at least 1500m horizontally and 1000 feet vertically from cloud with visibility 8Km. In Class F below FL100, VMC has the same cloud minima but a visibility of 5Km.
Version 2:
Distance from clouds 1500 m / 5 km horizontally, 1000 ft vertically Clear of clouds and ground in sight
Visibility (in-flight) 8 km at and above FL 100, 5 km below FL 100
From memory (I've got the relevant AIC printed at home), I believe that Version 1 relates to how it used to be until around 1997 and Version 2 is the current ICAO VMC minima.