come up against a brick wall —(also: come up against a blank wall) encounter an insurmountable obstacle or difficulty:
- So far, our efforts to stop the smuggling of protected species have come up against a brick wall.
Note: The expression is not equivalent in meaning to the phrase have one’s back against the wall—(also: be up against the wall) have run out of options; be pushed to the last extremity:
- I don’t give up easy and have had my back against the wall before. I don’t intend to give up without a battle.
run one’s head into a brick wall —(coll.) persist with smth. without making any progress (also: run one’s head into a stone wall):
- Trying to persuade him to change his plans is like running your head into a brick wall.