Seoul — U.S. Vice President Kamala Harris toured South Korea's heavily fortified border with the nuclear-armed North on Thursday, part of a trip aimed at strengthening the security alliance with Seoul. Pyongyang conducted two banned ballistic missile launches in the days before Harris's arrival, continuing a record-breaking streak of weapons tests this year.

At an observation post atop a steep hill overlooking North Korea, Harris peered through bulky binoculars as U.S. and South Korean soldiers pointed out features, including defenses, in the area.

"It's so close," she said.  "It's 50 meters away, ma'am," responded a military officer.                                                

Harris also visited the Panmunjom Truce Village — where then-U.S. President Donald Trump met the North's Kim Jong Un in 2019 — and talked to U.S. soldiers at Camp Bonifas in the Joint Security Area.

On the North Korean side of the border at Panmunjom, guards in hazmat suits could be seen watching as Harris was shown the demarcation line between the two countries, which have remained technically at war since a 1953 armistice agreement brought a halt to large-scale fighting.

Speaking at the Demilitarized Zone (DMZ), Harris said U.S. and South Korean soldiers were "serving shoulder to shoulder... to maintain the security and the stability of this region of the world."

She said the U.S. commitment to South Korea's defense was "ironclad," adding that the allies were "aligned" in their response to the growing threat posed by the North's weapons programs. The allies both want "a complete denuclearization of the Korean peninsula," but in the interim they are "ready to address any contingency," she said.

South Korean and U.S. officials have warned for months that Kim Jong Un is preparing to conduct another nuclear test.