Although the president's nine-minute speech urged de-escalation between Washington and Tehran, Trump said his administration "will immediately impose additional punishing economic sanctions" on the Iranian regime and revealed that he planned to ask NATO to "become much more involved in the Middle East process."

Trump's remarks have significantly diminished the likelihood of further armed conflict in the Middle East in the aftermath of the Iranian attack, which was precipitated by the killing of Tehran's top military commander in a U.S. drone strike last week.

Trump on Wednesday fiercely defended his order to remove Qassem Soleimani, the leader of Iran’s elite paramilitary Quds Force, from the battlefield, describing him as "personally responsible for some of the absolutely worst atrocities" and again insisting his death prevented future attacks on American interests.

The president also called upon the signatories of the 2015 multinational nuclear accord with Iran — China, France, Germany, Russia and the United Kingdom — to "break away from the remnants" of the pact and work together toward striking a new deal "that makes the world a safer and more peaceful place."

Just before turning from the news cameras and departing the podium, Trump made one of his most conciliatory overtures since the most recent period of heightened tensions with Tehran began roughly two weeks ago.

"Finally, to the people and leaders of Iran, we want you to have a future, and a great future. One that you deserve. One of prosperity at home, and harmony with the nations of the world," he said. "The United States is ready to embrace peace with all who seek it."

The White House address marked the president’s first public statement, on social media or otherwise, since he declared that “All is well!” in an optimistic tweet following the attack Tuesday evening.

“Missiles launched from Iran at two military bases located in Iraq. Assessment of casualties & damages taking place now. So far, so good! We have the most powerful and well equipped military anywhere in the world, by far!” Trump wrote, adding that he intended to comment further Wednesday morning.

Iranian Foreign Minister Mohammad Javad Zarif also issued a tweet Tuesday seemingly aimed at tamping down the potential for further aggression. The Islamic Republic does “not seek escalation or war, but will defend ourselves against any aggression," he wrote.

But Trump's assessment that Iran is now "standing down" broke with an ominous speech Iran's supreme leader delivered earlier Wednesday morning in the holy city of Qom. “They were slapped last night, but such military actions are not enough,” Ayatollah Ali Khamenei said of the Iranian missile salvo.

Wednesday was not the first time Trump, faced with the potential for a prolonged confrontation, has moved to defuse pressure on the U.S.-Iran relationship.

This past summer, as the two countries feuded over what the U.S. alleged were Iranian attacks on international oil tankers, the president called off a U.S. military strike against Iran after Tehran downed an American drone, saying he had decided the action was not worth the potential cost in lives.

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