Strange owl-like bird in Devon

A bird has been sat on a telephone pole outside my house (in Devon) for the last four hours. It's barely moved except to turn its head. I can see the wind ruffling its feathers. 

It looks fairly large - perhaps a foot tall. It's dark grey/black with a very short, squared off tail. It's head is large and neck/plumage around the neck is as wide if not wider than its body. The way it turns its head is like an owl - it's facing away from me but sometimes turns its head to face me without moving its body. It has a white face - bright, bright white. And looks like maybe it has little owl-like ear tufts. 

Its unbothered by people walking past, cars or native birds, just as the local birds are unbothered by it. It's just been sitting there for hours, watching the world go by. 

I have no clue what it is.