Iran's chief negotiator, Mohammad Bagher Ghalibaf, warned the United States on Sunday against issuing threats toward the Islamic Republic, saying that Iran's armed forces were prepared to respond.
"Do they not realize that if their threats had any effect, they would not have reached this point of desperation? We do not take American threats into account," Ghalibaf said after Trump threatened military action against Iran over its support for regional proxy groups.
"They would do better to be careful with their statements. Our armed forces are ready to respond in kind. No matter what they say, we are the ones who act," he added.
Earlier on Sunday, Trump wrote on his Truth Social platform: "Iran must immediately stop its highly paid proxies from causing trouble."
"If they don't, we'll hit Iran very hard again—just like we did last week, only harder!!!" he added.
Tensions involving Israel, Hezbollah, and Iran have repeatedly threatened diplomatic efforts in the region. However, by Sunday evening, there were no reports of new Israeli strikes or renewed fighting.
Ghalibaf's comments came as US and Iranian officials were holding talks in Switzerland with mediation from Qatar and Pakistan.
US Vice President JD Vance said there was an opportunity to “turn over a new leaf” with Iran.
The US is looking to get Iran locked into negotiations over its nuclear program amid concerns it may be used for military purposes, which Iran denies. Vance also is pushing Tehran to commit to keeping open the Strait of Hormuz, the critical waterway through which about a fifth of world traded oil passes.
But Trump's comments from afar, he spent much of the weekend at the presidential retreat at Camp David, Maryland, appeared to threaten to derail the negotiations.
The Iranian news agency Fars reported that US President Donald Trump's threats had led to the suspension of the talks, a claim that was not immediately confirmed by any official source.
Iranian state media said the talks had entered a “difficult phase” and recessed after the “publication of an insulting message by the U.S. President.” The Iranian delegation then met with Qatari mediators and left the negotiating site, state media said.
Despite the heated social media exchanges, an official with knowledge of the talks later confirmed the Iranian delegation remained engaged in the talks and has not indicated to mediators any intention to leave. The official requested anonymity due to the sensitivity of the talks.
