It is like I wrote i.e. you need to see the surface when flying VFR if
1) Your license is UK issued, and
2) You have neither an IMCR or an IR
The airspace or the country are irrelevant.
So e.g. an FAA PPL holder can fly VFR out of sight of surface in the UK. Currently he can do it in a G-reg too, due to the automatic validation of ICAO licenses (due to end April 2012, AIUI).