A firm message was delivered to the United States by Iran’s representative to the United Nations following deadly airstrikes over the weekend.

In a sharp escalation, the United States and Israel conducted coordinated airstrikes on Iran after stalled nuclear talks. The strikes targeted senior Iranian leadership at a compound in Tehran. Iran’s Supreme Leader, Ayatollah Ali Khamenei, and four family members were reported killed; Israel said the operation also targeted President Masoud Pezeshkian.

Donald Trump posted on Truth Social: “It’s a very simple message. They will never have a nuclear weapon. We’re going to destroy their missiles and raze their missile industry to the ground. It will be totally again obliterated.” He added: “Lay down your arms or face certain death.”

Iran announced the “first wave of extensive missile and drone attacks” across Israel, according to the New York Post, and signaled preparations to strike U.S. bases. State media warned of “the most devastating offensive operation in the history of the Islamic Republic of Iran’s armed forces,” and the Fars News Agency reported: “The most devastating offensive operation in the history of the Islamic Republic of Iran’s armed forces will begin toward the occupied territories and American terrorist bases in just moments.”

U.S. and Israeli airstrikes
Iran’s parliament speaker, Mohammad Bagher Qalibaf, condemned U.S. and Israeli leaders as “filthy criminals” and vowed “devastating blows,” saying: “You have crossed our red line and must pay the price,” and “We will deliver such devastating blows that you yourselves will be driven to beg.”

Trump later warned: “Iran just stated that they are going to hit very hard today, harder than they have ever hit before. THEY BETTER NOT DO THAT, HOWEVER, BECAUSE IF THEY DO, WE WILL HIT THEM WITH A FORCE THAT HAS NEVER BEEN SEEN BEFORE! Thank you for your attention to this matter! President DONALD J. TRUMP.”

Both sides signaled the conflict could intensify and potentially last weeks.

“I have one word only”
In an emergency UN session, Ambassador Amir Saeid Iravani condemned the attacks. According to United Nations News, the strikes breach international law, failing to meet the conditions for lawful self-defence and therefore “constitute a violation of Article Two.”

Iran has vowed to respond under the UN Charter’s Article 51, pledging to defend itself “without hesitation.”

During his speech, Iravani warned the U.S. to watch its tone. “I have one word only,” he said, according to VT. “I advise to the representative of the United States to be polite. It will be better for yourself and the country you represented, thank you.”

The U.S. ambassador, Mike Waltz, responded: “Frankly, I’m not going to dignify this with another response. Especially, as this representative sits here, in this body, representing a regime that has killed tens of thousands of its own people and imprisoned many more simply for wanting freedom from your tyranny.”

Labeled the strikes as a breach of the UN Charter
Iravani went on to label the strikes as unlawful: “This morning, the United States regime—jointly and in coordination with the Israeli regime—initiated an unprovoked and premeditated aggression against the Islamic Republic of Iran for the second time in recent months. This is not only an act of aggression; it is a war crime and a crime against humanity. The invocation to ‘preemptive attack,’ claims of imminent threat, or other unsubstantiated political claims, are unfounded legally, morally and politically.”

For its part, the U.S. maintains the operation was necessary to prevent Iran from threatening the world with nuclear weapons, Waltz said.

Meanwhile, UN Secretary-General António Guterres condemned both the strikes and Iran’s counteractions. “We are witnessing a grave threat to international peace and security,” he said. “Let me be clear: There is no viable alternative to the peace settlement of international disputes.”