A four-character idiom meaning a highly tense, touch-and-go situation where a small trigger could cause an explosion or conflict.
国境付近は一触即発の緊張が続いている。
Tensions remain touch-and-go near the border.
会議の雰囲気は一触即発で、誰も余計なことを言えなかった。
The meeting atmosphere was explosive; no one could say anything unnecessary.
両チームの対立は一触即発の状態だ。
The rivalry between the two teams is on the verge of explosion.