US Defense Secretary Jim Mattis on Friday visited the heavily fortified Demilitarized Zone (DMZ) that separates the two Koreas.

Mattis reiterated that the United States' goal was not to wage a war with North Korea but to diplomatically convince its leader to halt the country's nuclear program.

"North Korean provocations continue to threaten regional and global security despite unanimous condemnation by the United Nations Security Council," Mattis said in prepared remarks.

"As Secretary of State Tillerson has made clear, our goal is not war, but rather the complete, verifiable, and irreversible denuclearization of the Korean peninsula."

Standing alongside Mattis, South Korean Defense Minister Song Young-moo said Pyongyang would face a strong retaliation from the combined force of South Korea and the US if it chooses to use its nuclear and ballistic missiles.

"We together will continue to defend peace through strong will and strong might," he said.

Tensions between the US and North Korea have remained high after a series of weapons tests and threats by Pyongyang, which sparked a chain of threatening verbal exchanges between US President Donald Trump and the North Korean leader Kim Jong Un, where Trump threatened to rain "fire and fury" on the North.

This is Mattis' second visit to the Korean peninsula as Trump's defense chief and comes ahead of Trump's visit to Seoul next month.

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'Oppressive regime'

Mattis accused Pyongyang of building a nuclear arsenal to "threaten others with catastrophe," and termed the North "an oppressive regime that shackles its people, denying their freedom, their welfare and their human dignity in pursuit of nuclear weapons."

Mattis said while the US was in favor of a diplomatic solution to North Korea's nuclear program, it was prepared to take military action if the North did not rein in its nuclear ambitions.

Mattis, who arrived in South Korea earlier Friday, will meet with South Korean officials as part of annual ministerial talks on defense issues on the Korean peninsula.

In a bid to continue building pressure on Pyongyang, the US on Thursday imposed sanctions on 10 North Korean officials and organizations for "flagrant" human rights abuses, including a diplomat in China accused of forcing North Korean asylum seekers home.

ap/ng (Reuters, AP, dpa)