I looked into this in November/December last year, and came across a JAR regulation the gist of which was that you must get your initial class 1 done in the country in which the majority of your training occurs.
As I understand it (and I'd love to be proved wrong), this rules out getting a Dutch certificate, and then training in the UK.
If you want to know more, I can probably dig out the relevant sections from
www.jaa.nl
grob103