South Korea's chief nuclear envoy said on Monday that South Korea and the United States will seek ways to maintain dialogue with North Korea following the collapse of last week's working-level denuclearization negotiations between Washington and Pyongyang.

Lee Do-hoon, special representative for Korean Peninsula peace and security affairs, made the remark to reporters as he arrived at Dulles International Airport.

Lee's U.S. visit comes after American nuclear envoy Stephen Biegun and his North Korean counterpart Kim Myong-gil sat down in Stockholm together on Saturday but broke off talks hours later without an agreement.
  
Lee said he plans to stay in Washington until Thursday and hold several meetings with Biegun, adding to reporters that the two will discuss specific ways to maintain momentum for dialogue and how to realize tangible progress in that process.

Lee assessed that despite the lack of substantial results in the working-level negotiations, Washington and Pyongyang had the opportunity to fully understand each other's positions.

He said the two sides also left open the possibility of continuing the discussions, referring to the U.S. State Department's statement that it had accepted Sweden's invitation to return to Stockholm in two weeks to meet again with the North.