Calvo had the president on speaker phone, and posted a video of the exchange to his Facebook page. They haven't quelled tensions, but could be a foundation for a more diplomacy, according to US officials and others briefed on the process.
He told the governor, "You seem like a hell of a guy".
North Korea has announced plans to fire missiles into the sea near the island, a USA territory and key military base in the Western Pacific. "Some Guam residents told reporters that they anxious what might happen if North Korea's leader, Kim Jong-un, were actually to follow through". 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.
He then reassures Mr Calvo, who he describes as a "hell of a guy", telling him the U.S. military is "rock solid". "They should have had me eight years ago, or somebody with my thought process".
"There are two scenarios where we would go to war with North Korea", Graham explained.
"So, with all the criticism going on over there, from a guy that's being targeted, we need a president like you", said Calvo. And I wanted to call you and say hello. "So I'm just so thankful, and I'm glad you're holding the helm, sir".
"You've become extremely famous".
Mr Trump has said he would not allow Pyongyang to develop a nuclear weapon capable of hitting the United States.
The sheet urges people to take cover as quickly as possible, "under concrete structures or below ground if possible".
"I wish there would be less partisanship up there, this is a time of threats to the United States", said Calvo.
Trump praised the military, bashed an "obstructionist Congress" and told Calvo how tourism would be boosted for Guam without spending money.
Hawaii has also sought to prepare residents for the threat of a nuclear missile attack from North Korea, while stressing that the risk of a strike is low.
A giant inflatable chicken with a Donald Trump hairstyle has been placed near the White House by Taran Singh Brar, an Indian-origin activist, to protest the president's stand on releasing his tax returns, dealing with North Korea and engaging with Russian President Vladimir Putin.