UK Foreign Secretary David Lammy warned on Tuesday that Britain, France and Germany could invoke the United Nations “snapback” mechanism to restore suspended sanctions on Iran unless Tehran scales back its nuclear activities. Speaking at a parliamentary committee hearing, Lammy said the measure would impose “dramatic sanctions across nearly every front” of the Iranian economy if the Islamic Republic does not “get serious” about reversing its nuclear advances. A French diplomatic source, cited by Reuters, echoed the threat, saying the three European powers would be obliged to re-impose UN sanctions if no robust agreement is reached that safeguards European security interests. The source added that the issue was discussed in a phone call between French Foreign Minister Jean-Noël Barrot and Lammy ahead of a forthcoming Franco-British summit. The coordinated warnings underscore rising European frustration over Iran’s expanding nuclear programme and signal that the E3 is prepared to use the snapback provision embedded in the 2015 nuclear accord. Re-imposition of UN measures would revive sweeping restrictions on trade, arms transfers and financial dealings with Tehran, further isolating the Iranian economy.