One of the top Republicans on the Senate Foreign Relations Committee warned over the weekend that President Donald Trump had the ability “at his fingertips” to start a “very, very brief” offensive war against North Korea that would amount to “one of the worst catastrophic events in the history of our civilization.”

The dire comments came from Sen. James Risch (R-ID) during an appearance Sunday at the Munich Security Conference. The Idaho Republican, who is not known for bombast, said that Trump was prepared to launch a 21st century-style war that the world has never experienced before should North Korea continue to accelerate its nuclear program.

“The president of the United States has said, and he is committed to, seeing that Kim Jong-un is not able to marry together a delivery system with a nuclear weapon that he can deliver to the United States,” Risch said. “And anyone who doubts the president’s commitment to see that that doesn’t happen does so really at their own peril.”

The Trump administration has said that it is leaving military options on the table when it comes to deterring the nuclear threat from North Korea. Trump himself has directly taunted North Korea’s leader, Kim Jong Un, calling him “little rocket man” and vowing that the Korean peninsula will experience “fire and fury like the world has never seen” if Kim’s regime continues on its path toward an intercontinental ballistic missile strike that could reach the U.S. mainland.

Experts have warned that any military outbreak on the Korean peninsula would result in a humanitarian disaster. Risch, who serves on the intelligence and foreign relations committees and is expected to become the foreign relations committee chairman if Sen. Bob Corker (R-TN) does not run for re-election, appeared to echo those sentiments.

“If this thing starts, it’s going to be probably one of the one of the worst catastrophic events in the history of our civilization,” the 74-year-old senator said. “It is going to be very, very brief. The end of it is going to see mass casualties the likes of which the planet has never seen. It will be of biblical proportions.”

Despite the warnings of an all-out war on the Korean peninsula, Risch said the Trump administration has “never considered the strategy” of launching a so-called “bloody-nose” pre-emptive strike on North Korea, adding: “There is no such thing.”

“Sen. [Jeanne] Shaheen (D-N.H.) and I drilled down with the administration on that, and nobody knows where that came from,” Risch said.

The idea of a “bloody-nose” strike gained renewed attention following the publication of a Jan. 30 Washington Post op-ed by Victor Cha, who was nominated to be Trump’s ambassador to South Korea but was pulled because of his objections to such a proposal.

“A strike (even a large one) would only delay North Korea’s missile-building and nuclear programs, which are buried in deep, unknown places impenetrable to bunker-busting bombs,” Cha wrote. “A strike also would not stem the threat of proliferation but rather exacerbate it, turning what might be a North Korean moneymaking endeavor into a vengeful effort intended to equip other bad actors against us.”

Cha’s arguments illustrated the tension inside the administration over how to handle the North Korean threat. National security adviser H.R. McMaster has argued that such a strike should be left on the table, while Defense Secretary James Mattis and Secretary of State Rex Tillerson, who is spearheading efforts to reach a diplomatic solution, have downplayed its value.

“I’m going to use all the time available to me our diplomatic efforts will continue until that first bomb drops,” Tillerson said during a 60 Minutes interview that aired Sunday. “My job is to never have a reason for the first bomb to drop And we don’t know precisely how much time is left on the clock.”

More than 200,000 American citizens live in South Korea.

Risch’s office did not immediately respond to a request for comment on whether the senator’s assessment was based on conversations with Trump.