In this Aug 21, 2019 photo, then US special envoy for the DPRK Stephen Biegun, left, talks with his Republic of Korea (ROK) counterpart Lee Do-hoon, second from right, during their meeting at the Foreign Ministry in Seoul, ROK, Aug 21, 2019. Lee arrived on June 17, 2020 in Washington, where he is expected to hold consultations with Biegun. (KIM HONG-JI / POOL PHOTO VIA AP)

SEOUL - The Republic of Korea's (ROK) chief nuclear negotiator will visit officials in Washington on Thursday amid flaring tensions with the Democratic People's Republic of Korea (DPRK) after Pyongyang blew up an inter-Korean liaison office and threatened military action. 

Lee Do-hoon’s unannounced trip came days after DPRK blew up a joint liaison office in Kaesong, near the ROK border, declared an end to dialogue with Seoul and said it would return troops to border areas, counter to a 2018 peace agreement between the two countries’ leaders. 

Lee Do-hoon is expected to hold consultations with US officials, including Deputy Secretary of State Stephen Biegun who had led denuclearization negotiations with DPRK, ROK media reported. He is also expected to meet White House National Security Advisor Robert O’Brien

Lee is expected to hold consultations with US officials, including Deputy Secretary of State Stephen Biegun who had led denuclearization negotiations with DPRK, ROK media reported. He is also expected to meet White House National Security Advisor Robert O’Brien. 

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ROK’s Foreign Ministry declined to comment. ROK’s presidential press secretary said Lee’s trip had been planned for a long time, dismissing media reports that he was visiting as a special envoy. 

ROK television footage showed Lee arriving at Washington’s Dulles International Airport on Wednesday evening, where he declined to comment to reporters. 

Pyongyang has increasingly snubbed Seoul’s calls for engagement as efforts to restart inter-Korean economic projects stall due to international sanctions designed to rein in DPRK’s nuclear and missile programs. 

Tensions have grown, with Pyongyang taking issue over defectors in ROK sending propaganda leaflets into DPRK. 

Several defector-led groups regularly send back flyers carrying critical messages of DPRK leader Kim Jong-un, often together with food, US$1 bills, mini radios and USB sticks containing ROK dramas and news. 

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The Rodong Sinmun, the official newspaper of DPRK’s ruling Workers’ Party, said the demolition of the liaison office was the “first stage action” in its “holy war” aimed at punishing Seoul authorities for turning a blind eye to the defector’s campaign. 

“It was an iron hammer of stern punishment meted out to those who were having empty dreams while pursuing concealed hostile policy,” it said in a commentary. 

The newspaper also ran a series of articles and photos carrying angry ordinary citizens calling for retaliation and vowing to send anti-ROK leaflets over the border.