Just to verify what Nick has already correctly stated;
Below is an extract from the site
http://www.delti.com/press/english/deltiP66.html
mytyres.co.uk supports a move towards a minimum legal tread depth of 3mm - instead of the current 1.6mm. This would outlaw the majority of part worn tyres on sale in the UK. Binder explains: "In Germany motorists have been made aware the superior performance of tyres with at least 3mm tread depth remaining, mainly because of differing driving conditions and weather. That means many people change tyres well before the legal limit. The cast-offs are often exported, some of them finding their way to Britain.
Given the above Silver, looks like you and I both better think about some new rubber to kick the limey arses of these clowns that we are going with PMSL!
JJ