-/KOREA POOL/AFP via Getty ImagesBy JOOHEE CHO, ABC News

(SEOUL, South Korea) -- The U.S. Secretary of Defense Lloyd Austin has stressed that the American alliance with South Korea has “never been more important” given “unprecedented challenges" from North Korea and China in his first trip to the country on Wednesday.

On his first day of a three-day trip to South Korea, the first cabinet-level U.S. official of the Biden Administration to visit the country together with Secretary of State Antony Blinken, Austin’s entourage was greeted at the South Korean Ministry of Defense with an elaborate honor guard displayed by roughly 300 South Korean troops representing the various military services.

Filling the space of a football field, a typical military brass band played on the left side of the formation while a traditional Korean military band in full regalia played drums and horns on the the right side.

Austin’s South Korean counterpart, Minister Suh Wook, noted that “such a quick visit to the Republic of Korea by U.S. secretary Austin resulted from its high value for [the] Biden administration," in his opening comments before attending closed meetings.

Austin replied to Wook saying, “you and I can both agree that military readiness is a top priority, and that our combined readiness must ensure that we are ready to fight tonight if needed.”

Pentagon Press Secretary John Kirby provided a small glimpse of what was discussed in the meeting between the secretaries.

"The two leaders also addressed a broad range of defense issues, to include progress on transitioning wartime operational control, enhancing regional cooperation to protect the rules-based international order, and how to rejuvenate trilateral security cooperation," Kirby said in the readout obtained by ABC News. "Secretary Austin noted that the U.S. security commitment to the ROK remains ironclad, including the U.S. extended deterrent underpinned by the full-range of U.S. capabilities. Both leaders noted a commitment to supporting diplomatic efforts to achieve the denuclearization of North Korea consistent with United Nations Security Council Resolutions."

North Korean leader Kim Jong Un's powerful sister was quoted Monday saying that if the Biden administration "wants to sleep in peace for coming four years, it had better refrain from causing a stink at its first step.”

Asked for a response Tuesday, White House press secretary Jen Psaki said during an audio-only gaggle aboard Air Force One that "we don't have a direct comment or response to the comments made from North Korea" and that the “focus right now is on working with and coordinating with our partners and allies on -- on a range of issues, including security in the Korean Peninsula."

Psaki also confirmed earlier reports that the Biden administration has reached out to North Korea through “a number of channels as we always have had” since the inauguration, but has been ignored.

The two secretaries will hold so-called “two plus two” diplomatic and security talks on Thursday morning with their Korean counterparts, Foreign Minister Chung Eui-yong and Wook.

The officials will then be greeted by South Korean President Moon Jae-in at the presidential office in the afternoon before departing to Anchorage, Alaska.

Meanwhile, Blinken met with his South Korean counterpart, Eui-yong, and spoke about the shootings in the Atlanta area that killed eight people on Tuesday, including four women of Korean descent.

"I want to mention the attacks that happened just a few hours ago in Atlanta, in which several women were killed, including, we believe, four women of Korean descent. We are horrified by this violence which has no place in America or anywhere," said Blinken. "And I want to mention our deepest condolences to the families and friends of those who died, to anyone in the Korean community who is shaken and deeply disturbed by this incident ... We will stand up for the rights of our fellow Americans, Korean Americans, to be safe and to be treated with dignity."

Copyright © 2021, ABC Audio. All rights reserved.