They mostly do have the V label on vegan products.
However some just have it stated somewhere near the ingredients as "suitable for vegans" and then there's also some where they don't state anything but they are still made to a vegan recipe. But for the most part, at least for the kinds of things tourists will buy, you won't have to deal with the third one that much, if at all.
You'll be able to find loads of vegan restaurants in London via Happy Cow. It's been a few years since I've been down to London so I don't have any current suggestions. I do remember hearing there's a market (i think Camden) where there's a shop for vegan artisan cheese and that it's amazing.
We take for granted that if you engage in this community, you understand that veganism is about the animals. You either are vegan for the animals, or you are not (this is not to say that discussions about climate/environment/health are not allowed, of course)
No omni/carnist apologists. This is not a place where to ask to be hand-holded into veganims. Omnis coddling/backpatting is not tolerated, nor are /r/DebateAVegan-like threads
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They mostly do have the V label on vegan products.
However some just have it stated somewhere near the ingredients as "suitable for vegans" and then there's also some where they don't state anything but they are still made to a vegan recipe. But for the most part, at least for the kinds of things tourists will buy, you won't have to deal with the third one that much, if at all.
You'll be able to find loads of vegan restaurants in London via Happy Cow. It's been a few years since I've been down to London so I don't have any current suggestions. I do remember hearing there's a market (i think Camden) where there's a shop for vegan artisan cheese and that it's amazing.