Negotiations have stalled since a February summit between Kim Jong Un and President Trump in Hanoi, Vietnam, collapsed.
North Korea said Wednesday leader Kim Jong Un observed the test-launch of a super-large multiple rocket launcher.
The complete title of Anna Fifield's book is "The Great Successor: The Divinely Perfect Destiny of Brilliant Comrade Kim Jong...
North Korea said Thursday leader Kim Jong Un supervised the first test firing of a new multiple rocket launcher system.
Trump says his relationship with Kim remains good and that the missile tests were not a warning to the United States.
Last week, North Korea said it may lift its 20-month suspension of nuclear and missile tests.
The White House press secretary said Trump sent a letter and "correspondence between the two leaders has been ongoing."
North Korea's leader Kim Jong-Un will visit Russia for talks with Vladimir Putin this month, the Kremlin said Thursday.
Some experts say North Korea is trying to convey displeasure over the breakdown of the high-stakes nuclear summit last week.
John Bolton tried to make the case that Trump advanced America's national security interests by rejecting a bad agreement.