Disposable plasic knives are also banned in public, unless you are using it to eat. From https://www.gov.uk/buying-carrying-knives https://www.gov.uk/buying-ca

Disposable plasic knives are also banned in public, unless you are using it to eat. From https://www.gov.uk/buying-carrying-knives https://www.gov.uk/buying-carrying-knives stealth knives - a knife or spike not made from metal (except when used at home, for food or a toy)