I'm assuming this is about the British?
If that's the case then I say a hands off approach because it would be interesting to see if they develop any culinary skills. Who knows, maybe if their society evolves enough, they might even be capable of participating in economic trade with others. Stranger things have happened.
No...Not the British. More early human evolution where we saw homo sapiens existing alongside homo neanderthalensis, and wondering if that were to happen again (albeit possibly with a less related and more distinct species), how we might do things differently.