By Dan Merica, Kevin Liptak and Angela Dewan, CNN

(CNN) -- President Donald Trump further escalated his rhetorical standoff with North Korea Friday morning, suggesting the US was ready to respond with military force should the rogue nation "act unwisely."

In an early morning tweet, Trump appeared to warn the Pyonyang regime that the US military was on the verge of a strike. "Military solutions are now fully in place, locked and loaded, should North Korea act unwisely. Hopefully Kim Jong Un will find another path!" he tweeted.

It was the third consecutive day that Trump has used incendiary language to describe the threat posed by North Korea, which has responded with a threat to launch a series of missiles in the direction of the US Pacific territory of Guam.

On Wednesday, Trump said he would unleash "fire and fury like the world has never seen" on North Korea, which has conducted successful tests in recent months of intercontinental ballistic missiles the could reach the US mainland. On Thursday Trump said his threat may not have been tough enough and claimed past administrations had not done enough to take on North Korea.

A White House official downplayed Trump's latest declaration, telling CNN there were military plans for "just about any crisis we may face in the world" and they were regularly updated. "This isn't anything new," the official added.

Defense secretary James Mattis said on Thursday night that diplomatic efforts to contain the threat posed by North Korea remain the favored means for solving the crisis. He noted that the UN Security Council, in a rare display of unanimity over North Korea, passed a resolution that tightened sanctions against Kim's regime.

Region unsettled

The standoff has unsettled regional powers, some of which are scrambling to work out how to respond to the sudden escalation.

Russia's boosted its air defense systems in the far east, a report from state news agency RIA Novosti said on Friday.

An official at Japan's Ministry of Defense told CNN the country was deploying a US-supplied land-based missile interception system, known as a PAC-3, to four different locations, including three named by North Korean state media as under the flight path of the proposed strike at Guam. Officials aim for them to be in place by Saturday morning.

Calls for restraint

Neighboring powers urged restraint. Russia called on the Trump administration to keep calm, and on Friday Russian Foreign Minister Sergey Lavrov told state media that his country was working with China on a "double freezing" plan to address the threat.

"Kim Jong Un freezes any nuclear tests and any missile launches -- we mean ballistic missiles -- and the US and South Korea freeze large scale military exercises," Lavrov said, adding that North Korea regularly uses the drills to justify its missile tests and nuclear program.

"I believe that when it almost reaches the point of a fight, the one who is stronger and smarter must take the first step away from the dangerous line," he said.

China, North Korea's most influential ally and largest trading partner, has come under increasing pressure to intervene.

The state-controlled Global Times newspaper said in an editorial Friday that if North Korea launched missiles at the US, China should "stay neutral," sending a warning to Pyongyang that Beijing may not support the regime if it made a first move.

But the paper, whose views do not always represent official Chinese government policies, also said that if the US and South Korea took a first strike against North Korea, China should intervene.

In the crosshairs

At the center of the geopolitical storm is the tiny island of Guam, a US territory in the Pacific Ocean.

It's home to a US Navy base and the Andersen Air Force Base, from which American B-1B bombers conducted sorties over the Korean peninsula Tuesday, provoking the ire of Pyongyang's leadership and an escalating war of words between the US and North Korea.

On Thursday, North Korean state media KCNA said military leaders were working on a proposal to launch four intermediate-range Hwasong-12 missiles into the sea less than 25 miles off Guam's coast.

Guam's Homeland Security Advisor George Charfauros said Friday it would take 14 minutes for a missile fired from North Korea to reach Guam.

"It's a 14-minute flight time if all the factors are successful and if it gets through all the US defense layers in place," Charfauros told CNN. North Korea had previously said the flight time would be 1,065 seconds, or just under 18 minutes.

Ongoing rhetoric

But the tension continued Friday when North Korea said Trump was "driving the situation on the Korean peninsula to the brink of a nuclear war" with his continued rhetoric.

North Korean officials said the US "would suffer a shameful defeat and final doom" if it "persists in extreme military adventure, sanctions and pressure," according to a statement on North Korean state media, KCNA.

The statement went on to say that officials "vowed to mercilessly wipe out the provocateurs making desperate efforts to stifle" North Korea.

Other members of the Trump administration have sought to play down Trump's bellicose remarks. Speaking in California Thursday, Mattis warned North Korea that the US military was ready to take action, but said diplomatic efforts were the priority.

"I don't tell the enemy in advance what I'm going to do," Mattis said. "Our readiness, we are ready."

But he added that "the American effort is diplomatically led, it has diplomatic traction, it is gaining diplomatic results."

Mattis warned of the consequences of war. "The tragedy of war is well enough known, it doesn't need another characterization beyond the fact that it would be catastrophic," he said.

Analysts say that the escalation is unhelpful to resolving the increasingly tense situation in the Pacific.

"We're seeing a bit of response that we haven't seen before," says CNN military analyst Rick Francona. "What people are calling a threat to Guam, where they detailed the flight path, the flight time, the range, we've never really seen anything like this before... I think it rattled (the US administration) a little bit and caused them to (react) to this."

However, he says while the rhetoric from both leaders continues, "I don't think we're edging to an actual confrontation yet."