Trump advisers had no idea about a possible Kim Jong Un meeting until Trump tweeted: report
Standing in front of the flags of their two countries, Donald Trump and Kim Jong Un made history in Singapore. (AFP / SAUL LOEB)

President Donald Trump met with Kim Jong Un in North Korea Sunday, but the meeting was a complete surprise to his aides, according to a report from the Wall Street Journal.

Trump was leaving the G-20 meeting when he tweeted Saturday that he was headed to North Korea to "say Hello(?)!" to Kim at the border. It came as such a surprise that they were forced to scramble for 24 hours to prepare.

"The administration hadn’t begun to plan for a possible meeting until the president tweeted," the Journal cited those familiar with the discussion. Despite comments from Trump hinting at a meeting, there wasn't anything set up or scheduled.

"That touched off a race among aides to arrange with one day’s notice a meeting between the two leaders, whose previous summits required months of preparation," the report continued. "Administration officials earlier in the week had advised reporters not to expect a Trump-Kim encounter."

Even Ivanka Trump was cagey about the ordeal, telling South Korea’s first lady at a G-20 dinner that her father would have an "update" for the South Korea side about the event, which was less than 24-hours away.

"In the hours leading up to the encounter Sunday, during which Mr. Trump became the first sitting U.S. president to step inside North Korea, it remained unclear whether it would happen—another instance of the impulsive diplomacy that has defined the Trump presidency," the Journal reported.

Trump reportedly said in an interview that he "might" meet with Kim while visiting President Moon Jae-in in Seoul. The White House asked for the information to be deleted for security reasons.

"Two days later, on Wednesday, Mr. Moon told foreign journalists visiting Seoul that the U.S. and North Korea had engaged in 'behind the scenes' talks about a third summit between the two countries’ leaders," said the Journal.

Read the full report at The Wall Street Journal.