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.
North Korean leader Kim Jong-un has threatened to fire missiles at Guam, home to USA military bases in the South Pacific, in an escalating war of words over Pyongyang's nuclear-weapons program.
Donald Trump has told Guam's Governor North Korea's threat to launch a missile strike near the remote Pacific island will boost tourism, while assuring the politician the U.S. stands behind the territory "1,000 per cent".
"We're going to do a great job, don't worry about a thing", Mr Trump responded.
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".
"You know, they're showing so much, it's such a big story in the news and it just looks like a lovely place", he says.
"Good morning, good morning", the president is heard saying to Calvo.
"Mr President, as the Governor of Guam, representative of Guam's people, and as an American citizen, I felt never more safe and confident with you at the helm", the Governor said with a smile.
"Eddie, I have to tell you, you've become extremely famous", said the president, who telephoned from Bedminster, New Jersey, where's he on a working vacation. All over the world they're talking about Guam and they're talking about you.
Calvo agrees. "It's paradise, " he says.
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. He doesn't talk so much anymore. "I will be convening the unified coordination group, which includes myself and the rear admiral, to discuss the readiness of our military and our local first responders".
"We are the best in the world by a factor of five", he says.
While Guam is generally calm about the escalating threats of a missile attack, some were not thrilled by the tone of the conversation between the two men.