Look, you are talking about the leader of the Conservative Party, a party that claims to be 'for working people', which either demonstrates that to them 'work' means 'the sort of things they do in Wall Street or London City', or they are just full of weasel words; you tell me. My guess is, they don't know and they don't care how this is supposed to work, he is just posturing.
However, I think there is a more realistic side to this - as it is now, there aren't really any rules, or if there are, these sites are getting away with simply ignoring them and hiding behind 'free speech'. The police or other authorities can't do anything against them, because they have to follow the law - so if you see this as a problem and want to tackle it, you have to change the law so police are allowed to take action. As I see it, it is about putting pressure on porn sites to start taking things seriously, because they haven't bothered until now.