As I said, I did some research into this an it seems that according to DEFRA (our government department for such things) most seed coming into the UK (including things like cabbage and bean seed) will need a “phytosanitary certificate” :
http://www.defra.gov.uk/planth/publi...r/impguide.pdf - Appendix A, Section III)

It also seems that all seed sent to US needs the same certificate or an import permit.
http://ecfr.gpoaccess.gov/cgi/t/text...1.1.6.7&idno=7)

Sorry Gardenhappy…but this seems a bit of a long-winded process for me…

Raquel