Secretary of State Rex Tillerson Rex Wayne TillersonGary Cohn: 'I haven't made up my mind' on vote for president in November Kushner says 'Alice in Wonderland' describes Trump presidency: Woodward book Conspicuous by their absence from the Republican Convention MORE said in an interview Sunday that President Trump wants to continue working toward a diplomatic solution to the North Korean threat "until the first bomb drops."

During an interview on CNN's "State of the Union," Tillerson said Trump is trying to "motivate action" on North Korea, adding that the president wants to be clear that he has military options on the table.

"The president has also made clear to me that he wants this solved diplomatically," Tillerson said.

"He is not seeking to go to war."

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He said Trump has made it clear Tillerson should continue his diplomatic efforts in North Korea.

"Those diplomatic efforts will continue until the first bomb drops," Tillerson said.

However, White House National Security Adviser H.R. McMaster said the president would do whatever is necessary to prevent an attack from North Korea on the U.S.

"Our president has been really clear, he's not going to permit this regime and Kim Jong Un to threaten the United States with a nuclear weapon," McMaster said on "Fox News Sunday."

"He's going to do anything necessary to prevent that from happening and what Kim Jong Un should recognize is that if he thinks the development of this nuclear capability is keeping him safer, it's actually the opposite," he continued.

Tensions between the U.S. and North Korea have escalated in recent months.

Trump earlier this month said it was a waste of time for Tillerson to try to negotiate with North Korea.

"I told Rex Tillerson, our wonderful Secretary of State, that he is wasting his time trying to negotiate with Little Rocket Man," the president tweeted earlier this month, adding that Tillerson should "save [his] energy."

— Julia Manchester contributed.