In this file photo taken on June 12, 2018, US President Donald Trump, right, and North Korea's leader Kim Jong-un shake hands following a signing ceremony during their historic US-North Korea summit, at the Capella Hotel on Sentosa island in Singapore. AFP-Yonhap

The United States is stepping up preparations for another round of negotiations with North Korea on dismantling the regime's nuclear weapons program, a South Korean official said Friday.

Lee Do-hoon, South Korea's chief nuclear envoy, provided the update to reporters in Washington after holding a series of meetings with U.S. officials handling the negotiations.

"The U.S. side is accelerating its internal preparations for follow-up negotiations with the North," he said. "The U.S. is forming a negotiating team made up mostly of State Department officials, and they are actively coordinating their stance on denuclearization and other practical issues."

Negotiations between the U.S. and North Korea have reportedly moved slowly since U.S. President Donald Trump and North Korean leader Kim Jong-un struck a denuclearization deal at their historic summit last month.

Kim committed to the "complete denuclearization" of the Korean Peninsula in return for security guarantees from the U.S.

U.S. Secretary of State Mike Pompeo flew to Pyongyang last week to flesh out the agreement but publicly reported little tangible progress in its implementation.

He has also established a working group within the department to handle the issue. It includes Alex Wong, deputy assistant secretary for East Asian and Pacific Affairs; Ben Purser, deputy assistant secretary for international security and nonproliferation; and Mark Lambert, acting deputy assistant secretary for Korea.

The team supports U.S. Ambassador Sung Kim's negotiations with North Korean Vice Foreign Minister Choe Son-hui.

"It appears that North Korea and the U.S. will soon hold the next round of negotiations," Lee said. "Based on my conversations on this trip, I plan to continue coordination with the U.S. on our joint strategy for (North Korea's) denuclearization." (Yonhap)