I can think of the following, which I think is roughly equivalent but not slang:
Αυξάνω τις πιέσεις
There are also two other phrases, which are used on slightly different occasions; namely:
Σφίγγω τον κλοιό (it implies a literal or metaphorical war against someone but sometimes it's equivalent to "to tighten the screw")
Βάζω το μαχαίρι στον λαιμό κάποιου (to give no choice to someone -put initial pressure)