entre le marteau et l'enclume
- (literally) between the hammer and the anvil
- (by extension, idiomatic) between a rock and a hard place; between the devil and the deep blue sea
In the idiomatic sense loosely identical to “be in a bad situation”; not as strong as between a rock and a hard place and it doesn't catch the idea of being forced to take into account antagonist interests (the “hammer” and the “anvil”). When a decision is hard to make between one or the opposite one, neither of them being ideal.