Defense Department Press Secretary Brig. Gen. Pat Ryder is seen holding a daily press briefing at the Pentagon in Washington on Thursday in this image captured from the department's website. (US Department of Defense)

WASHINGTON -- The United States remains ready and capable to deter and counter any potential aggression against South Korea under its extended deterrence, a Pentagon spokesperson said Thursday, in apparent opposition to possible nuclear armament of its Asian ally.

South Korean President Yoon Suk Yeol said earlier this week that Seoul may deploy tactical nuclear weapons "or possess its own nuclear capabilities" should North Korean provocations intensify.

Yoon's remark followed an unprecedented number of ballistic missiles launched by North Korea. Pyongyang fired 69 ballistic missiles, including eight intercontinental ballistic missiles last year, far exceeding its previous annual record of 25.

Defense Department Press Secretary Brig. Gen. Pat Ryder said the issue was for the South Korean government to address when asked during a daily press briefing.

However, from a US standpoint, he said, "Our policy continues to remain focused on the complete denuclearization of the Korean Peninsula."

"A lot of this has to do with the fact, from a regional security and stability standpoint and non-proliferation, in terms of preventing the potential chance for the use of nuclear weapons, and so, from a United States perspective, again, our policy remains very clear on denuclearization," he added.

Ryder also emphasized US extended deterrence provided to South Korea and other allies in the region, which he earlier said includes the "full range of US nuclear capabilities."

"It's important also to remember that the Republic of Korea falls under that extended deterrence umbrella. And so, in addition to the US forces that are assigned there on the peninsula, our allies in the region to include South Korea are part of that," he told the press briefing.

The US currently maintains some 28,500 troops on the Korean Peninsula.

When pressed about the possibility of the US nuclear umbrella failing to deter aggression, the Pentagon spokesperson said, "To date, it has worked and it has worked very well."

A state department spokesperson stressed the importance of close cooperation between the US and its Asian allies -- South Korea and Japan -- in dealing with the threat posed by North Korea.

Ned Price said Pyongyang poses a threat to the US, South Korea and Japan that the three countries "take extraordinarily seriously."

"The most challenging threat to regional peace and security we face at the moment is that from the DPRK, namely, its nuclear weapons program, its ballistic missile program, as well," he told a daily press briefing at the state department, referring to North Korea by its official name, the Democratic People's Republic of Korea.

"We discuss these issues -- alliances, effectiveness and readiness -- with our Japanese allies. We discuss them with our South Korean allies. But we are also very focused on the trilateral relationship because we know that with the trilateral relationship in some ways, the sum is greater than its constituent parts," he added. (Yonhap)