President Trump and German Chancellor Angela Merkel managed to fit in a joint news conference during her brief three-hour visit to the White House, her first trip outside Germany since she narrowly won re-election to her fourth term. North Korea, trade and Iran and the Iran deal were high on the agenda.

Mr. Trump declined to say whether he has met with North Korean leader Kim Jong Un directly. But he did say he's gotten a "kick" out of watching the failures of past administrations in dealing with North Korea, and said a lot has changed in the last few months. "You know, the name calling and a lot of other things," said Mr. Trump, who has called Kim "little rocket man." Kim, for his part, has called Mr. Trump a "dotard" and a "frightened dog." Mr. Trump thanked Merkel for her help with the "maximum pressure campaign" on North Korea.

"I will be meeting with Kim Jong Un in the coming weeks, we look forward to that," Mr. Trump said, claiming his administration will "not repeat" the mistakes of past administrations.

In a meeting with Merkel before lunch, Mr. Trump said he doesn't think Kim is "playing," although other administrations were "played like a fiddle" because the U.S. had different leaders. The North and the South signed a pledge Friday to seek a formal end to the Korean War by the end of the year and to rid the Korean peninsula of nuclear weapons. They have not specified how they would achieve this. 

Merkel's visit follows a three-day visit from French President Emmanuel Macron, after which Macron said he believes Mr. Trump will leave the Iran nuclear deal. Merkel also seemed to indicate that whether the U.S. stays in the Iran deal is up to Mr. Trump. As the deadline for certifying the Iran deal quickly approaches, and the administration has suggested Mr. Trump might pull out, Mr. Trump addressed Iran and the deal in general terms. He did not say whether he has decided to stay in the deal.

"We must ensure that this murderous regime does not even get close to a nuclear weapon," Mr. Trump said.

The president declined to say whether he would consider using military force in Iran, if necessary. 

"I don't talk about whether or not I'd use military force ... but I can tell you this, they will not be doing nuclear weapons ... you can bank on it," the president said.

Another issue of international importance is up to Mr. Trump, Merkel said — the exemption from the steel and aluminum tariffs levied by Mr. Trump is about to expire. 

Mr. Trump also addressed the anticipated opening of the U.S. embassy in Jerusalem next month, saying he "may go."

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