1763, "blind alley, dead end," from French impasse "impassable road; blind alley; impasse" (18c.), from assimilated form of in- "not, opposite of" (see in- (1)) + passe & [..]

deadlock: a situation in which no progress can be made or no advancement is possible; "reached an impasse on the negotiations" blind alley: a street with only one way in or o [..]

a point in esp. labor negotiations at which reaching an agreement is impossible because neither party is willing to compromise or change position

On a number of occasions and in various forms, negotiations have taken place in order to secure a political settlement in Northern Ireland. When these became deadlocked without any sign of a breakthrough they were described as having reached an 'impasse'.

An impasse occurs when after engaging in good faith negotiation, mediation, factfinding with a mediator and post fact-finding negotiations, the parties are unable to reach an agreement. Various laws a [..]

(n) a situation in which no progress can be made or no advancement is possible(n) a street with only one way in or out

a road with no exit; a cul-de-sac a deadlock or stalemate situation in which no progress can be made *(situation in which no progress can be made; not used in the chess sense of ''stalemate'') [..]