President Trump is facing dual nuclear threats from Iran and North Korea, and is reacting strongly to one but saying little about the other. On Monday, the president said Iran was "playing with fire" after it surpassed a uranium stockpile limit set by the 2015 nuclear deal, defying the agreement for the first time in response to Mr. Trump pulling the U.S. out of it last year. But North Korea continues to produce material for nuclear weapons despite U.S. efforts, including an historic weekend meeting between the president and Kim Jong Un.

The Trump administration is reportedly split on what demands to make of the North Korean leader as it prepares to return to the negotiating table -- possibly considering some concessions including providing humanitarian aid to the isolated totalitarian state, reports CBS News' Chip Reid. As for Iran, the White House is vowing to keep up its campaign of "maximum pressure" through sanctions until Tehran reverses course.

In a new interview with Fox News' Tucker Carlson, Mr. Trump continued to push for talks with Iran, even though Tehran has said it won't open a direct dialogue until the harsh sanctions imposed by the White House are lifted.

"You can't let Iran have a nuclear weapon. And you can't let certain other countries have nuclear weapons. Too devastating," Trump said. "Hopefully at some point they'll come back and they'll say, 'we're going to make a deal.' We'll see what happens."

The White House released a statement Monday vowing to keep maximum pressure on the regime in Tehran. Iran's foreign minister mocked the White House's assertion that, "even before the deal's existence, Iran was violating its terms." Foreign Minister Javad Zarif issued a sardonic one-word response on Twitter: "Seriously?"

Iran had remained in compliance with the terms of the nuclear deal since its implementation in October 2015, according to the International Atomic Energy Agency (IAEA), the global watchdog agency tasked with monitoring Iran's nuclear activities.

Different approach with Kim

Democrats, meanwhile, have continued to slam the president's foreign policy approach following his meeting in the Korean Demilitarized Zone with Kim Jong Un.



"He pats the guy on the back and gets nothing in return," senior Democratic Sen. Chuck Schumer charged on Monday.

But U.S. Navy Adm. Sandy Winnefeld (Retired), a former Vice Chairman of the Joint Chiefs of Staff, told CBS News that he believes the meeting has put the president is in a better position with North Korea than he was in when talks broke down earlier this year.

"He has everything to gain if he can get a deal across the table with Kim Jong Un that actually works and denuclearizes North Korea," Winnefeld said.

A North Korea expert who has experience negotiating with the country for the U.S. government told CBS News, meanwhile, that the criticism of Mr. Trump's border encounter with Kim fails to take into account the considerable weight that North Korea's government-run media are lending to the meeting.

The expert, who spoke off the record to CBS News, said the meeting came at a hugely symbolic time for North Koreans -- during a month when the regime has often heightened its anti-U.S. rhetoric. The domestic coverage of the meeting in North Korea, by the state-run news agency, suggested that the it could signal an end to what the regime has long termed the "hostile policy" of the U.S.

Unlike the English version, the Korean-language article by the KCNA news agency suggested the two countries may no longer be "deeply rooted enemy states."

The expert told CBS News that these nuanced references could give Kim more ability to maneuver against critics of his reform policies within his own government, and more latitude to engage in serious negotiations with the U.S.

On the other hand, Winnefeld said that Iran's actions put it on a shorter path to having enough uranium to build its first nuclear weapon -- but that would still take at least a year.

"I think the difference between Iran and North Korea is a matter of personality of the two regimes," Winnefeld said. "Kim Jong Un… sees an opportunity to bond with the president and potentially use him, and the Iranians are not so willing to compromise."

Winnefeld added that the Trump administration is going to have to be very careful not to provoke an open conflict with Iran.

Asked about the prospect of a U.S. military attack on Tehran, Mr. Trump said told Fox News, "hopefully we don't have to do anything."