EU Imposes Fresh Sanctions on Iran Over Assassination Plots

The bloc faces conflicting pressures as it tries to salvage its nuclear deal while confronting hostile behavior in the region

BRUSSELS—The European Union imposed its first sanctions against Iran since the nuclear accord was implemented three years ago, as European diplomats warned their Iranian counterparts that the bloc wouldn’t tolerate further alleged Iranian attacks and assassinations in Europe.

Tuesday’s sanctions, which add two Iranian individuals and a unit of the Iranian intelligence services to the bloc’s terror list, follow alleged plots against Iranian opposition figures in Denmark and France. The targets’ assets will be frozen and other...