"This is why what Kim Jong-un is doing is very, very risky", McMaster said, referring to the North Korean dictator. "But we're closer to war than we were a decade ago", McMaster said.
U.S. President Donald Trump has offered fiery warnings for North Korea, saying that the U.S. military was "locked and loaded".
Pressed on his "nothing imminent" statement, Pompeo said: "What I'm talking about is, I've heard folks talking about that we have been on the cusp of a nuclear war".
Senior U.S. national security officials said Sunday that a military confrontation with North Korea's is not imminent, but they cautioned that the possibility of war is greater than it was a decade ago.
Pompeo said it would not be surprising if North Korea sought to strengthen its nuclear arsenal and even test another missile.
Pompeo also defended Trump's "fire and fury" comment. The CIA chief described Kim as "rational" and responsive to "adverse circumstances".
"The president has made it very clear to the North Korean regime how America will respond if certain actions are taken", Pompeo said.
Trump wrote on Twitter on Friday that U.S. "What he does is he asks us to make sure that we have viable options for him, options that combine diplomatic, economic, and military capabilities", he said.
"We're not closer to war than a week ago".
China's president, Xi Jinping, made a plea for cool-headedness in a phone conversation with Trump on Saturday, urging both sides to avoid words or actions that could worsen the situation.
Referring to Kim, Trump added: "If he utters one threat. or if he does anything with respect to Guam or any place else that's an American territory or an American ally, he will truly regret it, and he will regret it fast".
State-run China Central Television quoted Xi as telling Trump the "relevant parties must maintain restraint and avoid words and deeds that would exacerbate the tension on the Korean Peninsula".
In response, Mr Trump said North Korea should expect "big, big trouble" if anything happened to Guam.
The top US intelligence official said on Sunday he would not be surprised if North Korea tested another missile, given that it had two tests in July, amid rising tensions between the two nations.
The tough talk capped a week in which long-standing tensions between the countries risked abruptly boiling over.
But despite the escalating rhetoric from Trump, McMaster said the threat of war with North Korea has not dramatically increased over the past few days, though he underscored the seriousness of the problem.
In an interview with German newspaper group RND, Gabriel said the manoeuvres "could lead to North Korea using the opportunity for renewed provocation, for example, by firing an intermediate-range missile at Guam".