WASHINGTON - Republican presidential candidate Donald Trump has criticized President Barack Obama and the Iran nuclear agreement at a rally in the US state of Wisconsin, saying he was “like a baby” after expressing that Tehran has yet to follow the “spirit” of the deal.

“I hear Obama is very unhappy with Iran because he feels they haven’t lived up to the ‘spirit’ of the agreement. What the hell did he think was going to happen? He is like a baby. He’s like a baby,” Trump said Saturday during a campaign rally in Wisconsin on Friday night.

“How we have this man as a president is so embarrassing. Anybody in their right mind would have known what he is getting into,” the billionaire businessman added.During a news conference Friday at the end of the Nuclear Security Summit in Washington, President Obama criticized Iranian leaders for undermining the “spirit” of last year’s agreement, even as they stick to the “letter” of the pact.

In comments, Obama denied speculation that the United States would ease rules preventing dollars from being used in financial transactions with Iran, in order to boost the country’s engagement with the rest of the world. Instead, Obama claimed, that Iran’s troubles even after the lifting of sanctions under the nuclear deal were due to its continued support of Hezbollah, ballistic missile tests and other aggressive behavior.

“Iran so far has followed the letter of the agreement, but the spirit of the agreement involves Iran also sending signals to the world community and businesses that it is not going to be engaging in a range of provocative actions that are going to scare businesses off,” Obama said at a press conference.“When they launch ballistic missiles with slogans calling for the destruction of Israel, that makes businesses nervous.”

“Iran has to understand what every country in the world understands, which is businesses want to go where they feel safe, where they don’t see massive controversy, where they can be confident that transactions are going to operate normally,” he added. “And that’s an adjustment that Iran’s going to have to make as well.”Months after the U.S. and other global powers lifted sanctions against Iran in exchange for limits on its nuclear programme, Iranian leaders complain that they have yet to reap the benefits.

“Our banking trade, our efforts to return wealth from their banks, various kinds of businesses that require financial services - all of these are still facing problems,” Supreme Leader Ayatollah Ali Khamenei said in an address last month. “When we investigate the issue, it becomes obvious that [the banks] are afraid of the United States.”

Despite the lifting of sanctions, American companies are still banned from doing business in Iran and foreign banks are prohibited from using the U.S. dollar for their Iranian dealings. At the same briefing, Obama lashed out at Trump for comments the Republican frontrunner had earlier made about nuclear proliferation.

Earlier this week, Trump suggested that allowing Japan and South Korea to have nuclear weapons would save the US the cost of defending its East Asian allies. Trump also argued that if the US was not willing to use an atomic bomb, then “why are we making them?”Trump also said that he would “never take any of my cards off the table” regarding the possibility of using an atomic bomb even against Europe.

The remarks prompted President Obama to question Trump’s fitness for Oval Office. “We don’t want somebody in the Oval Office who doesn’t recognize how important that is.”"The person who made the statements doesn't know much about foreign policy or nuclear policy or the Korean Peninsula or the world generally," Obama added.

Obama described the US nuclear umbrella for Japan and South Korea, in place of their own arsenals, as "one of the cornerstones of our presence in the Asia Pacific," which has provided the U.S. peace, prosperity and flowing commerce. "It has prevented the possibilities of a nuclear escalation and conflict," he added. "You don't mess with that. It's an investment that rests on the sacrifices that our men and women made" in World War II.