Trump, who has ramped up his rhetoric throughout the escalating crisis with North Korea, told the murmuring crowd of world leaders on Tuesday that "it is far past time for the nations of the world to confront" Kim Jong Un and said that Kim's "reckless pursuit of nuclear weapons" poses a threat to "the entire world with an unthinkable loss of human life".
"I don't think you've heard the end of it", Trump said.
Following a meeting Wednesday with Palestinian Authority President Mahmoud Abbas, Trump told reporters "I have decided" how to proceed.
Tillerson said he had been surprised when Trump publicly announced he had reached a decision. By the time Trump departed late Thursday for his golf resort in New Jersey, the leaders of both North Korea and Iran had thumbed their noses at Trump's bombast, responding with their own insults.
This may have been Trump's finest speech as president.
Other world leaders have said the deal can not be renegotiated.
Trump's withering critique Tuesday included an accusation that Iran's government "masks a corrupt dictatorship behind the false guise of a democracy", while ruthlessly repressing its people and exploiting the limits of the nuclear deal.
"To put it simply, we meet at a time of both huge promise and of great peril", he said.
But he declined to say what he had decided.
Will the United States abandon the nuclear deal?
Q: Richard Haass, president of the US Council on Foreign Relations, has compared Trump with George W. Bush, saying the US president's United Nations speech resurrects Bush's "axis of evil" with only change that Iraq has fallen off and North Korea and Iran remain. "What should motivate countries like North Korea or others to enter into negotiations in the future when the one example of such a deal is being destroyed?" he said.
The agreement on Iran's nuclear program was reached between Iran and six global mediators (the United Kingdom, Germany, China, Russia, the United States, and France) on July 14, 2015.
"Moderation is the inclination as well as the chosen path of the great Iranian people".
Nikki Haley, the US ambassador to the United Nations, began laying the groundwork for the move earlier this month when she suggested in a speech at the conservative American Enterprise Institute that Iran is at the very least violating the spirit of the agreement.
Trump has said repeatedly that he is inclined not to certify Iranian compliance after having twice found the country compliant at earlier deadlines. The judgment of the USA intelligence community, the IAEA, the monitoring mechanism, our closest allies, even the Trump administration itself has certified twice that Iran is complying with this deal. "It was not an angry tone at all, it was a very, very matter-of-fact exchange about how we see this deal very differently".
Asked whether the agreement could survive without the US, he said "it's a bit early or premature to hold discussions about such questions", adding that the "Europeans want to preserve it".