Biden administration sends mixed signals on US soldier who crossed into North Korea

The State Department has yet to engage with foreign governments on the case.

"We're looking into this," White House press secretary Karine Jean-Pierre told ABC News Senior White House Correspondent Mary Bruce, adding that President Joe Biden had been briefed on the matter and that U.S. officials were still gathering the facts.

"The White House, the Department of Defense, the State Department, and also the U.N. are all working together to ascertain more information and resolve this situation," Jean-Pierre said.

Defense Secretary Lloyd Austin said the Pentagon had reached out to North Korean military officials on the matter and that he was "absolutely foremost concerned about the welfare of our troop," identified by U.S. officials as 23-year-old Pvt. Travis King.

Although King is now the first American in nearly five years known to be detained by North Korea -- a country notorious for its harsh prison conditions -- the State Department indicated it would take a restrained approach as officials said they had seen no clear sign that King wanted to return to the U.S.

Hours after the incident, spokesperson Matthew Miller said the State Department had not directly reached out to any foreign governments about the case because it did not see such outreach as "an appropriate or necessary step."

While the U.S. does not have a direct diplomatic relations with North Korea, limited consular services are often made available to American citizens in the country through Sweden, which serves as the protecting power for the U.S.

Miller said the State Department may attempt to extend that assistance to King.

"I will just say that, as always, the safety and security of any American overseas remains the top priority for the United States," he said. "Whatever we can do to resolve this situation we will of course not hesitate to take the appropriate step.

Sweden has also served as an effective intermediary in other cases involving Western nationals imprisoned by Pyongyang.

Before crossing into the Korean demilitarized zone, King spent 47 days at a South Korean detention facility following an altercation with local and was set to return to the U.S. to face disciplinary action, according to one U.S. official.

Prior to King, Bruce Byron Lowrance was the last American known to be held by North Korea. Lowrance illegally crossed over the border from China in October 2018 and was jailed for roughly a month before ultimately being deported with minimal international intervention.

North Korea has released several other American prisoners in recent years, including Otto Warmbier, the University of Virginia student who entered the country as part of a guided group tour in 2015 and was convicted of stealing a propaganda poster during his stay.

Due to unknown causes, Warmbier slipped into a vegetative state shortly after his sentencing. Pyongyang allowed the student to be repatriated to the U.S. in 2017 while he in a coma, but he died less than a week after his return.

But during President Biden's time in office, communication with the hermit kingdom has been virtually nonexistent, with the administration maintaining it is ready to engage with Pyongyang without any preconditions but receiving no substantive response.

Beyond its human rights record and strict isolationism, North Korea poses significant national security and diplomatic challenges to the U.S., including through its resurgent nuclear program and frequent ballistic missile launches -- violations of United Nations Security Council resolutions.

In the past, American leaders have been able to rely on China to steer North Korea, but both Beijing's willingness and ability to intercede has increasingly coming into question.

During the Secretary of State Antony Blinken's engagement with his Chinese counterpart earlier this month, North Korea was not even on the agenda, officials said.

ABC News' Molly Nagle and Matt Seyler contributed to this report.