The US withdrew tactical nuclear weapons from the peninsula in the early 1990's.

McCain also said Washington should make clear to North Korean leader Kim Jong-un that "if he acts in an aggressive fashion, the price will be extinction."

North Korea conducted its sixth and most powerful nuclear test last week, claiming it successfully detonated an H-bomb that can be mounted on a long-range missile.

In July, it carried out two tests of an intercontinental ballistic missile that could theoretically reach the mainland US.

The senator said the US should put more economic pressure on China to compel it to rein in its wayward ally.

"We've got to tell the Chinese: It will hurt the United States if we lose some trade with you, but I'm telling you now, something is going to have to change," he said. (Yonhap)