UK Designated Airports

[NorthPorts]

Not sure if this post should be here or the Biz GA thread, apologies if wrong.

I'm trying to find the official list of UK designated airports for customs. I know the GAR lists them and there are Police / Terrorism & Customs designations. Some have one or other, some have both.

I understand the "designated" bit is the legal reference. I have checked the Air Nav order & the CEMA, both have references but no list.

Any clues as to where the official legal act or official reference is that lists designated airports?

Thanks