"Negotiations on the final agreement will not begin if the threats continue. Honor your signature," writes Abbas Araghchi on X, referring to paragraph 13 of the memorandum of understanding with the US.
Exactly what threats he is referring to is unclear, but as recently as Monday, Donald Trump once again threatened to "finish the job."
"We can knock out their bridges in an hour, we can knock out their energy supply," the president said at the White House.
Iran and the United States signed a declaration of intent in June to end the Iran-Iraq war, in which the parties agreed to refrain from threats and military force for 60 days. Both countries have since accused each other of violating the agreement.
On Tuesday night, the United States accused Iran of firing missiles in the disputed Strait of Hormuz, according to Axios.
