WASHINGTON -- US Defense Secretary James Mattis refused to address calls for redeploying US nuclear weapons to South Korea, saying the allies maintain “open discussions” about North Korea‘s growing nuclear threat.

South Korea’s conservative parties have doubled down on their push to bring US tactical nuclear weapons back into the country since North Korea conducted its sixth and most powerful nuclear test on Sept. 3.

“We have a nuclear deterrent and its location is immaterial,” Mattis told reporters Wednesday on a flight to North Dakota, where he was to visit a US Air Force base handling two legs of the nuclear triad -- strategic bombers and intercontinental ballistic missiles.
 

“We have very open, transparent and candid discussions about the severity of the North Korean threat with our allies South Korea and Japan,” he said.

South Korea is under the US nuclear umbrella. But US tactical nuclear weapons were withdrawn from the peninsula in the early 1990s.

Mattis said there is a longstanding policy to keep the location of the nuclear arsenal a secret.

“It‘s part of the deterrent that they (the enemy) cannot target them all,” he said.

US broadcaster NBC recently reported that the Trump administration is considering nuclear options for South Korea and Japan, including the reintroduction of US tactical nukes and their own nuclear armament.

The South Korean government has repeatedly rejected talk of going nuclear, saying it goes against the principle of denuclearizing the peninsula.

Mattis said the latest nuclear device tested by the North was a “large one,” but would not confirm whether it was an H-bomb as claimed by Pyongyang.

Last week, a senior US administration official said there is “nothing inconsistent” with the North Korean claim so far, although the assessment is still ongoing. (Yonhap)