Home Depot co-founder and Trump supporter Ken Langone warns that tension with North Korea is “the single greatest threat since World War II.”

North Korea’s Fourth of July test of an intercontinental ballistic missile represents a “very ominous” and “extremely dangerous situation” for the world, Langone told CNBC on Thursday.

Langone warned CNBC that President Donald Trump must soon resolve the conflict with North Korean leader Kim Jong Un,

“This is the trigger, OK? This could be the trigger of a calamity in the world,” he says.

“We’re looking at the single greatest threat since World War II,” he said.

Langone, a longtime Republican supporter and co-founder of Home Depot, spoke after Trump warned he is considering a “severe” response to North Korea after it claimed it successfully launched a missile capable of hitting Alaska.

Langone said Trump and Russian President Vladimir Putin, who are set to meet at the