In Doctor Who episode S10E4 Knock Knock, the Doctor is suspicious about the background of the landlord, and at one time he asks him if the landlord knows who the current Prime Minister is.
But the landlord refuses to answer; he changes the topic instead.
Sure, I'm aware of the out-of-universe answer: the landlord is a figure of mystery, who we know nothing about, who may not be of this time, or not of this world. And this just serves to deepen our suspicions.
But what about in-universe? In the end,
the landlord turns out to be a normal human, not a time traveller or an alien (this may be a bit of a spoiler, sorry)
so why would he have difficulties with knowing about current affairs? Why circumvent the question who the current Prime Minister is?