France, Germany, and the United Kingdom have warned they are prepared to reinstate UN sanctions on Iran if it fails to return to nuclear negotiations.

Axar.az, citing Reuters, reports that in a letter to the UN seen by the paper, the E3 foreign ministers said they would trigger the “snapback” mechanism unless Tehran agrees to a diplomatic solution before the end of August or accepts an extension.

The warning follows last month’s “serious, frank and detailed” talks with Iran in Istanbul — the first face-to-face meeting since Israeli and US strikes on its nuclear facilities. None of the three governments immediately commented.