Having been to the UK many times over the last 20 years, I would suggest that it is too late.
Downtown London looks like any middle eastern city, chuck full of burka clad people (I would say burka clad women, but who can tell?).
England's sandhead problem is just like ours. Stop any and all public assistance of any kind to all the filthy illegal sandheads and they might stop coming to the UK. However, rotted pig meat sandwiches should be provided to any hungry sandhead if they 'promise' to go back to the desert.