France, Britain and Germany have initiated the process of triggering the " snapback mechanism " that automatically reimposes all United Nations sanctions on Iran over its nuclear program, saying Iran has willfully departed from their 2015 nuclear deal that lifted the measures.

The U.N. sanctions that were in effect before the 2015 deal included a conventional arms embargo, restrictions on ballistic missile development, asset freezes, travel bans and a ban on producing nuclear-related technology.