come to an impasse
To reach a point or problem that is insurmountable or from which there is no possible exit, progress, or negotiation. After hours of bitter debate, the two parties came to an impasse, and the discussion was left for the following day.
come to an impasse
Fig. to reach a deadlock, stalemate, etc., in a situation. (Alludes to a blocked roadway.) The committee has come to an impasse in its deliberations.