"We're going to do a great job, don't worry about a thing", Mr Trump responded. All over the world the world, they're talking about Guam, and they're talking about you, and I think - tourism, I can say this, your tourism, you're going to go up like tenfold with the expenditure of no money, so I congratulate you.
North Korean military on Thursday said it would prepare a plan by mid-August to strike Guam, a U.S. island territory in the Western Pacific, with intermediate missiles.
"I have to say, Eddie, you're going to become extremely famous".
Trump's call came as North Korea is threatening an attack on Guam amid escalating tensions over North Korea's continued push to develop nuclear weapons capable of reaching the USA mainland.
"Do not look at the flash or fireball - It can blind you", it said.
He told Calvo: "You notice that he hasn't spoken recently?"
Earlier this week, North Korea threatened to launch four missiles toward Guam.
If a warning is issued, Guam residents should take cover quickly - in a concrete structure, preferably underground - and stay there until instructed otherwise, according to the fact sheet titled "Preparing for an Imminent Missile Threat".
The President and Chief of Staff General John Kelly called Gov. Eddie Baza Calvo and assured him that they are behind Guam 1,000-percent. "They should have had me eight years ago..."
"Good Morning, my dear people of Guam", began the governor.
North Korea says its Hwasong-12 missiles would take just 1,065 seconds to complete their 3,356km flight over Japan before splashing down in waters off the coast of Guam.
Further, North Korea declared its military is "capable of fighting any war the US wants is now on the standby to launch fire into its mainland, waiting for an order of final attack".
Xi's call came hours after Trump warned North Korea that the USA military is "locked and loaded", and as the Pentagon said the United States and South Korea plan to proceed with a joint military exercise in 10 days.
Mr. Trump plans to meet Mr. Xi later this year in what the White House called "a very historic event".