The president said he'd tell Kim, "I wouldn't let that happen under my auspices".
"I can't show you the letter obviously, but it was a very personal, very warm, very nice letter", Trump told reporters outside the White House.
"The book says that security camera footage from Kim Jong Nam's last trip to Malaysia showed him in a hotel elevator with an Asian-looking man who was reported to be a US intelligence agent", Reuter noted.
North Korea's leader Kim Jong Un, right, walks with President Donald Trump during a break in talks at their historic US-North Korea summit, at the Capella Hotel on Sentosa island in Singapore. Beijing is believed to have maintained a good relationship with Kim, and it was speculated that in the event of a regime collapse in North Korea, China may have sought to install Kim as their chosen candidate to run the country as a client state.
"I'm concerned how Jong-un, who merely resembles my grandfather [former North Korean leader Kim Il-sung], will be able to satisfy the needs of North Koreans", he wrote.
Earlier this month, Salon spoke with former U.S. Ambassador Michael McFaul, who represented the Obama administration in Russian Federation. Trump and Kim last met early this year in Hanoi but failed to reach a denuclearization agreement.
North Korean leader Kim Jong Un sent his sister to the border with South Korea on Wednesday to offer condolences for the death of a former first lady, in the first significant interaction between the two countries in months. "That's very important to me". "It just hasn't resulted in things that make us better off".
Yet his National Security Adviser John Bolton and acting Secretary of Defense Patrick Shanahan have both said that the tests violated United Nations resolutions.
Asked about the CIA's links to Kim Jong Nam, Trump said: "I don't know about that".
"North Korea has tremendous potential, and he'll be there".
But given how little the USA knew about Kim Jong Un when he succeeded his father and came to power in 2011, any insights into who he is and what he is like would have been valuable, according to some former officials.
Trump said at the time that those launches did not pose a problem in his eyes, although his advisers called them a violation of U.N. Security Council resolutions.
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The optimism that the two leaders generated in Singapore all but evaporated in February when a second summit, in Vietnam, dramatically fell apart without even a recommitment to the general goals outlined in a statement signed in Singapore.
"Its nuclear and ballistic missile programs not only are left intact, they are also advancing and growing, since they were never bound to an agreement", said Soo Kim, a policy analyst at the RAND Corporation and a former Central Intelligence Agency analyst.