"Kim Jong-un, the world always thought he was not a responsible leader".
McMaster said the threat from North Korea to the world is "very, very clear".
Discussing the escalating war of words between the USA and North Korea over the latter's rogue nuclear program, Ellison raised eyebrows by saying the North Korea's despotic leader was acting better than the US president.
In a letter, 64 House Democrats urged Secretary of State Rex Tillerson to make sure Trump's rhetoric is met with the "utmost caution and restraint".
North Korean workers have held rallies in support of Kim Jong-un's regime as they country continued to rail against fresh United Nations sanctions that cut off $1billion in worldwide trade.
The Labour leader's intervention comes after China's president warned the USA and North Korea not to exacerbate tensions after Mr Trump said Kim would "truly regret" military action.
Of Trump's "fire and fury" remarks, Mattis said: "The rhetoric is up to the president". I don't think we are there yet.
Mr Rudd, who just returned to the United States from a trip to China, said "the Chinese baseline conclusion" is Mr Trump's threat of unilateral military action against North Korea was just "one huge bluff".
"And what none of us know is whether President Trump will ultimately accept a position in history which says, "I'm the guy and it was on my watch that this state finally crossed the threshold of constituting a threat to the USA mainland".
Clapper said the U.S. and North Korea could "blunder" into global military conflict as they exchange escalating hostilities.
According to the White House, Trump and Xi affirmed that the recent adoption of a new UN Security Council resolution regarding North Korea was an important and necessary step toward achieving peace and stability on the Korean Peninsula.