WASHINGTON — The Iran nuclear deal will lead to a nuclear holocaust, Donald Trump warned Sunday.

Still, if he’s elected president, the GOP front-runner won’t “rip up” the deal as some of his Republican primary opponents have said they would. Speaking in a prerecorded interview Sunday morning on NBC’s “Meet the Press,” Trump said he’d “police” the deal to mitigate its impact.

Trump questioned claims that the deal could simply be cancelled once it has gone into effect. “It’s very hard to say, ‘We’re ripping it up,” he argued. Other Republican contenders — including Senator Ted Cruz and Governor Scott Walker — have said that they would “rip up” the agreement if they were elected.

Instead, Trump offered a different plan.

“I’m really good at looking at a contract and finding things within a contract…,” he said. “I would police that contract so tough that they don’t have a chance. As bad as the contract is, I will be so tough on that contract.

“The people who negotiated that deal — [Secretary of State John] Kerry and his friends — are incompetent,” he complained. Trump suggested that America should stop using “political hacks” and “ambassadors,” but should rely instead on his colleagues in the business world to negotiate deals.

Trump emphasized that no matter what, Iran would have already received what he calculated as $150 billion in sanctions relief by the time he would take office. The White House has downplayed that number, arguing that much of the funds that Iran would receive under the deal is already committed to servicing debts.

Trump, however, said that he only found out “about last week” that “if the deal is rejected [by Congress], they still get all that money.

“I couldn’t believe it,” Trump stated.

“Iran is going to be unbelievably rich and unbelievably powerful and Israel is in real trouble,” Trump warned. “[Iran is] going to have nuclear weapons. They are going to take over parts of the world that you wouldn’t believe. And I think it’s going to lead to a nuclear holocaust.”

Republican presidential candidate businessman Donald Trump speaks with reporters after arriving at the Iowa State Fair on August 15, 2015 in Des Moines, Iowa.  (Aaron P. Bernstein/Getty Images/AFP)

Republican presidential candidate businessman Donald Trump speaks with reporters at the Iowa State Fair in Des Moines, Iowa, August 15, 2015. (Aaron P. Bernstein/Getty Images/AFP)

Trump said that if he had been involved in the over 18 months of negotiations that led up to the Joint Comprehensive Plan of Action, he would have established red lines; he “would have told [Iran] up front that you will never get your $150 billion back” and demanded the release of the Americans held by Iran as a precondition for sitting down at the table.

Appearing at the Iowa State Fair on Saturday, Trump said that Obama and Kerry hurt Israel through the recently signed nuclear agreement.

“Israel was sold out by Kerry and Obama,” he claimed. “You cannot let Iran have a nuclear weapon. You can’t have it. When they march down the street saying ‘Death to Israel. Death to the United States.’ You can’t let that happen.”

Trump is a vocal supporter of Israel and a harsh critic of President Barack Obama’s policy toward Israel.

“I have many Jewish friends that support Obama and I say, ‘Why?’ and they can’t explain why. They support him, they give him money, they give him campaign contributions,” Trump told radio host Michael Savage in February. “This is the worst enemy of Israel.”

Trump’s candidacy may have originally been viewed by many Washington pundits as a flash in the pan, but in the most recent national poll, the real-estate mogul polled at 25% support among Republicans. His next-closest opponent according to the Fox News poll published Sunday — neurosurgeon Ben Carson — trails with a mere 12% of Republicans supporting him.

Both Trump and Carson have made a point of presenting themselves as Washington outsiders, dismissive not only toward the Obama administration, but towards the way that business as usual is done by both parties.

Trump spoke at length about foreign policy during the NBC interview. He suggested that US military involvement should be subsidized by the states that America intervenes to assist, and proposed seizing oil wells from the Islamic State and holding the resources as vehicles for funding care for US military and veterans.

But the candidate who, during the first GOP debate, repeated the complaint that the Iran deal provided for a 24-hour rather than 24-day appeals process for on-site inspections, seemed on shaky ground when asked where he gets his military advice from.

“Well, I watch the shows,” Trump offered. “You know, when you watch your show and all of the other shows and you have the generals.” He went on, when pressed, to cite UN Ambassador John Bolton and Ret. Army Colonel and NBC military analyst Jack Jacobs as people he would turn to.

JTA contributed to this report.