The letter to UN Secretary-General António Guterres and the UN Security Council says the three European powers are “committed to use all diplomatic tools” at their disposal “to ensure Iran does not develop a nuclear weapon,” unless Tehran meets the set deadline.
The foreign ministers from the so-called E3 group threaten to use a “snapback mechanism” that was part of a 2015 international deal with Iran that eased UN Security Council sanctions.
Under the deal, which terminates in October, any party to the accord can restore the sanctions.
All three countries have stepped up warnings to Iran about its suspension of cooperation with the UN nuclear watchdog, the International Atomic Energy Agency.
That came after the 12-day war between Israel and Iran in June.
“We have made clear that if Iran is not willing to reach a diplomatic solution before the end of August 2025, or does not seize the opportunity of an extension, E3 are prepared to trigger the snapback mechanism,” foreign ministers Jean-Noël Barrot of France, David Lammy of Britain and Johann Wadephul of Germany said in the letter.
