President Trump on Tuesday signaled he is close to ditching the Iran nuclear agreement struck by former President Barack Obama, by saying the deal is an "embarrassment to the United States" in his first address to the United Nations General Assembly.

"We cannot let a murderous regime continue these destabilizing activities while building dangerous missiles and we cannot abide by an agreement if it provides cover for the eventual construction of a nuclear program," Trump said.

"The Iran deal was one of the worst and most one-sided transactions the United States has ever entered into," he added. "Frankly, that deal is an embarrassment to the United States, and I don't think you've heard the last of it, believe me."

Trump delivered that stark message just a day after he said, "you'll see very soon" when asked whether he would stick to or abandon the agreement, which most Republicans say fails to force Iran to abandon its nuclear program.

Trump promised during the 2016 campaign to end the Iran nuclear agreement, which he has called the "worst deal ever negotiated," but the State Department has so far recertified the deal to Congress under Trump.

Trump attacked the Iranian government for using its wealth to fund the dictatorship of Syrian President Bashar Assad, prop up the civil war in Yemen, and "undermine peace" in the Middle East.

"The Iranian government masks a corrupt dictatorship behind the false guise of a democracy. It has turned a wealthy country with a rich history and culture into an economically depleted rogue state whose chief exports are violence, bloodshed and chaos," Trump said. "The longest suffering victims of Iran's leaders are, in fact, its own people. Rather than use its resources to improve Iranian lives, its oil profits go to fund Hezbollah and other terrorists that kill innocent Muslims and attack their peaceful Arab and Israeli neighbors."

In his address to more diplomats and world leaders from 193 countries, the president urged Iran's government to release all Americans and citizens of other country's it is currently holding in captivity and said the regime must "stop supporting terrorists, begin serving its own people, and respect the sovereign rights of its neighbors."

"The entire world understands that the good people of Iran want change, and other than the vast military power of the United States, that Iran's people are what their leaders fear the most," Trump said.

"Oppressive regimes cannot endure forever and the day will come when the people will face a choice. Will they continue down the path of poverty, bloodshed and terror? Or will the Iranian people return to the nation's proud roots as a center of civilization, culture and wealth where their people can be happy and prosperous once again?" he asked.