The hermit nation threatened to attack Guam, which is a USA overseas Pacific territory.
Despite the inflammatory language that Trump has been using, North Korea hasn't responded in the same way that it normally does, suggesting that Pyongyang has taken a step back to consider its options.
"We are with you 1,000 per cent, you are safe", he adds.
I can say this, your tourism, you're going to go up like tenfold, with expenditure of no money, so I congratulate you. The island, roughly the size of Chicago and home to about 160,000 people, is about 2,200 miles southeast of North Korea. "You are safe", Trump told Calvo at the start of the three minute call. "It looks attractive, you know I'm watching - it's such a big story in the news". "We encourage everyone to go through their lives and live them like you would do any other day". During the conversation Trump also noted how much everyone around the world is talking about and focused on Guam after the missile attack threats by North Korea.
On Wednesday, Mr Trump followed up his "fire and fury" warning with a boast about USA nuclear capabilities.
Calvo said earlier this week that "there is no change in the threat level resulting from North Korea events".
Elon Musk's AI bot beats world-class gamers at Dota 2
What OpenAI has learned with Dota 2 might just translate to other fields where understanding subtleties can be crucial to success. Players control one of dozens of different characters with varying abilities, and compete to collect items and control territory.
Activists who are advocating Guam's independence from the United States argue that the presence of the military installations has made the island a magnet for attack. "This is a time of threat to the United States". Guam now hosts major American military might like a bomber fleet and a missile defense system.
"I think we should get more out of this relationship than what we are getting now", he said. Calvo, in response, said he has "never felt more safe or more confident" than with Mr. Trump at the helm. "So I'm just so thankful, and I'm glad you're holding the helm, sir".
The president then takes a jab at his predecessors, telling Calvo, "They should've had me eight years ago or at least somebody with my thought process because that was the time".
The phone call follows the President's latest tweet in which he wrote the military is "locked and loaded" if North Korea acts "unwisely".
Responding to the threats, Trump has threatened North Korea with "fire and fury" as well as tweeting that the U.S. was "locked and loaded".