Normally I don’t get too much into another nation’s business, but Americans have an affection for the British. Here’s some helpful suggestions:
KEEP your knives and if you have any, your firearms…
If you are attacked, go for the throat then GUT your attacker and LEAVE. Go home and disassemble your knife and clean it thoroughly with bleach and alcohol (And your hands, etc.). Reassemble and put it back in your pocket.
Socks are a great place to hide things…like a knife! Most people carry weapons around their waist, and that’s where most people look for them.