take it or leave it
Definition from Wiktionary, the free dictionary
- (idiomatic) A situation has to be accepted without change, or rejected outright.
- That's the deal: take it or leave it.
- 2007, Michael C. Donaldson, David Frohnmayer, Negotiating For Dummies, Published by For Dummies, page 169 
- Even when you are making your final offer, presenting the deal as a "take it or leave it" proposition is a mistake.
accept the situation without change