Take a look at this versatile adjustable wrench, opens up to 38mm wide. Not only can it remove your bottom bracket, but it can also be handy for various bike, car, and household tasks. Channellock also has a similar wrench, but I am not sure if it is available/sold in UK.

https://www.amazon.co.uk/Bahco-9031T...22&sr=8-8&th=1