A man watches the news showing US soldier Travis King on screen, at a his home in Seoul, South Korea, Sept. 27. EPA-Yonhap

An American soldier who crossed the inter-Korean border into North Korea in July is in U.S. custody after his release by the reclusive regime, senior U.S. administration officials said Wednesday, capping an intense diplomatic operation facilitated by Sweden and China.

Speaking at a press briefing, the officials said Pvt. Travis King has been transferred out of North Korea across the border with China, and that he appears to be "in good health and good spirits" ahead of his return home.

The announcement of his release came shortly after the North's official Korean Central News Agency (KCNA) reported Pyongyang decided to "expel" him following an investigation, during which it said he confessed to having "illegally intruded" into the North's territory.

King crossed the military demarcation line separating Korea during a tour to the Joint Security Area in the Demilitarized Zone (DMZ) on July 18 ― a rare unauthorized trip that led to his detention in the North.

"We are very pleased to announce this morning ... the U.S. government has successfully facilitated Pvt. Travis King's departure from the DPRK," a senior official said on condition of anonymity. DPRK stands for the North's official name, the Democratic People's Republic of Korea.

"We are grateful to the Swedish government for its diplomatic role in serving as the protecting power for the United States in the DPRK and to the government of the People's Republic of China for its assistance in facilitating the safe transit of Pvt. King," the official added.

Having left the North, King arrived in the Chinese border city of Dandong and flew to another Chinese city, Shenyang, and then to Osan Air Base in South Korea, where he was transferred to the Department of Defense, before departing for the U.S., according to the Department of State.

Hours earlier, the KCNA said North Korean authorities conducted an investigation, where he said he had "ill feelings" about the U.S. military and society.

"Travis King confessed that he illegally intruded into the territory of the DPRK as he harbored ill feeling against inhuman maltreatment and racial discrimination within the U.S. army and was disillusioned about the unequal U.S. society," KCNA said in its English-language report. "The relevant organ of the DPRK decided to expel Travis King."

A TV screen shows a file photo of American soldier Travis King during a news program shown in Seoul Station, July 24, AP-Yonhap

Earlier this month, the U.S. learned via Sweden that the North wanted to release King, another administration official said, calling Sweden as the "primary interlocutor" that helped King in being released.

China helped facilitate King's safe transit across the border and played a "very constructive role," but not a mediating one, according to the officials.

Asked whether there were any concessions to the North in return for King's release, the first official said, "None."

"Our focus right now is on Pvt. King's health and ensuring that he receives all appropriate support before reuniting with his family," the official said.

Pyongyang's decision to set King free "without concessions" raised cautious hopes for the resumption of diplomacy as nuclear talks between Washington and Pyongyang have been stalled since 2019 following a no-deal summit in Hanoi in February that year.

The officials reiterated Washington's willingness to reengage with Pyongyang.

"The U.S. government remains very open to the possibility of diplomacy with the DPRK ... This incident to our minds demonstrate that keeping lines of communication open even when ties are strained is a really important thing to do and can deliver results," the official said. "We again stand by … ready for any further diplomacy that might be possible."

Asked to explain the next procedures facing King, a third official highlighted the government's priority on the soldiers' "reintegration."

"Our focus right now is caring for him and his family and we'll work through all those administrative status questions following completion of his reintegration," the official said.

Later in the day, U.S. National Security Advisor Jake Sullivan issued a statement extending his appreciation to Sweden and China for their diplomatic efforts. Pentagon press secretary Brig. Gen. Pat Ryder also released a similar statement on King's release.

The North first confirmed King's detention on Aug. 16 and claimed the U.S. soldier expressed willingness to seek refuge in the North or a third country.

Shortly after the North's first confirmation of King's detention, the U.S. Department of Defense said the alleged comments by King could not be verified.

Observers had said Pyongyang could seek to use King for propaganda purposes or as a bargaining chip to wring out concessions from Washington.

King faced legal trouble during his service in South Korea. He was sentenced to labor in a South Korean prison workshop from May 24 to July 10 after failing to pay a fine for damaging a police patrol car last year.

On Oct. 8, South Korean police apprehended King for assault at a nightclub in western Seoul. He reportedly did not cooperate with police officers demanding his personal information and kicked the door of their vehicle.

King had been set to return to the United States on July 17, where he would have faced additional disciplinary action, however, he managed to evade boarding his flight at Incheon International Airport and was able to join a JSA tour the next day which provided him with the opportunity to cross the DMZ. (Yonhap)