Congressman Mac Thornberry, who chairs the powerful House Armed Services Committee that provides civilian oversight to the Pentagon, said the administration of President Donald Trump is closely studying its options.
"The administration is very seriously looking at what would be involved with military options when it comes to North Korea," Thornberry told a group of reporters.
Training efforts "are very serious," he added.
"The military has preparations under way, and hopefully they will not be needed."
Defense Secretary Jim Mattis has repeatedly insisted that efforts to resolve the North Korea crisis should be diplomatically led, though he has said the Pentagon always plans for any contingency.
Tensions on the Korean peninsula and between Pyongyang and Washington have been sky-high for months, after North Korean leader Kim Jong-Un repeatedly test-fired missiles potentially capable of carrying a nuclear warhead and hitting the United States.
He also authorized the detonation of North Korea's most powerful nuclear device to date.
Though the US military routinely trains on the Korean peninsula with South Korean counterparts, The New York Times reported Sunday that a series of drills in the United States suggest a new focus on readying the military for conflict with North Korea.
"If you are going to ask men and women to risk their lives on behalf of the nation, we owe them not only the best military equipment but also the best training and preparation that our country can provide them and I think that's part of what's going on," Thornberry said.
But the rhetoric picked back up again Tuesday, when North Korea denounced President Donald Trump's tweeted message that he has a bigger nuclear button than Kim as the "spasm of a lunatic" and the "bark of a rabid dog."
On January 2, Trump had written on Twitter: "Will someone from his depleted and food starved regime please inform him that I too have a Nuclear Button, but it is a much bigger & more powerful one than his, and my Button works!"
Further adding to jitters, residents in Hawaii were subjected to an erroneous alert Saturday warning them that a missile was inbound.
Emergency management officials later admitted "the wrong button was pushed" during a shift change.
Speaking to reporters ahead of a summit in Canada aimed at increasing pressure on North Korea, Mattis said the Korea situation is "sobering."
"This effort right now is firmly in the diplomatic realm. That is where we are working it," Mattis said Monday on his way to Vancouver, while cautioning that military options remain.
"That is what we want to have come out of this -- let the diplomats know that they are backed up by the force of arms," he said, according to a Pentagon transcript.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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