Experts have suggested the symbolic footage is the precursor for a major policy announcement.
State media outlet KCNA said it boosted the country's strategic nuclear deterrence. South Korea's defence minister said it was an engine test.
An isolated conference centre on the outskirts of Stockholm was the setting on Saturday for the US and North Korea to resume nuclear talks.
Amidst joint US military exercises with South Korea the North fires an unidentified projectile and declares talks with the south "over"
North Korea have fired a series of projectiles from an area known to be used as a military base, South Koreas military have said.
U.S. student Otto Warmbier died six days after being released.
Kim said his personal relationship with the American president remains good and that they could exchange letters at "any time."
Analysts believe Trump’s tweet revealed internal divisions within his administration over what approach to take with North Korean leader Kim Jong Un following the collapse of last month’s Hanoi summit.
Malaysia drops murder charge against Indonesian woman in Kim Jong Nam case