Please don't do this, there is enough geo-blocking crap going on on the web as it is, it's discriminatory and often inaccurate. This is not international law, so unless you run business in the UK you can just ignore it (and based on your suggestion you are not). Don't punish ordinary people for stuff they have no say in.
I also expect this law will be revised or just fizzle out eventually anyway like previous impractical digital "laws" made in the UK.