Trump then says, "We're going to do a great job for you".
"We are with you 1,000 per cent, you are safe", he adds.
In the phone call Mr Trump goes on to praise the island's beauty, which he says he has seen in news reports about the missile threat.
Tensions between North Korea and the U.S. escalated this week amid increasingly heated rhetoric between Washington and Pyongyang.
Trump has been escalating his rhetoric against North Korea, but says he hopes "it will all work out". All over the world they're talking about Guam and they're talking about you.More news: European Union slaps sanctions on additional North Korean nationals
Mr Calvo responded by agreeing his home was "paradise" and had "99 per cent occupancy". So, with all the criticism going on over there from a guy who is being targeted, we need a president like you.
Calvo posted a video of the conversation to Facebook.
Earlier this week, North Korea threatened to launch four missiles toward Guam. "But you're going to be taken care of". "Fallout radiation loses its intensity fairly rapidly".
The Government has instructed residents to be proactive and create emergency supply kits, a family emergency plan and a list of concrete shelters in their vicinity. Good morning. I just wanted to pay my respects, and we are with you 1,000 percent. Asked if the US was going to war, he said cryptically, "I think you know the answer to that".
He then reassures Mr Calvo, who he describes as a "hell of a guy", telling him the United States military is "rock solid".More news: Putney Bridge jogger push suspect eliminated from inquiry
The president called the USA military "incredible, "rock solid" and "the best in the world by a factor of five".
The Morning Joe panel discusses Defense Secretary Jim Mattis' warning for North Korea following President Trump's comments this week regarding "fire and fury", as well as NK's consideration of firing a missile near Guam.
Tensions have escalated between the US and North Korea as the communist regime continues testing and expanding its nuclear program, reporting this week that it can now fit nuclear warheads on missiles.
He concluded, "May God bless the people of Guam, and may God bless America".
On Wednesday, Mr Trump followed up his "fire and fury" warning with a boast about USA nuclear capabilities.More news: Rubio defends Trump's promise of 'fire and fury'
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