"President Moon told President Trump that he plans to send a special envoy to North Korea, who will reciprocate the visit by North Korea's special envoy Kim Yo-jong and confirm details of issues discussed during a high-level North Korean delegation's South Korea visit," the press release said.

Kim Yo-jong, North Korean leader Kim Jong-un's younger sister, delivered Kim's invitation for Moon to visit Pyongyang for what would be a third inter-Korean summit during her three-day visit to South Korea from Feb. 9.

Cheong Wa Dae did not disclose Trump's reaction to the South Korean leader's plan to send a special envoy to the communist state.

The White House also made no mention of that portion of the call.

"President Trump and President Moon noted their firm position that any dialogue with North Korea must be conducted with the explicit and unwavering goal of complete, verifiable, and irreversible denuclearization," it said in a readout. "The two leaders committed to maintain close coordination."

The State Department, when asked to comment on Moon's plan, said the allies are in close contact.

"The United States is latched up very closely with South Korea," department spokeswoman Heather Nauert said during a regular press briefing. "We have many conversations with our ally. Those conversations continue. We have a broad range of conversations with them. We share the principle of the denuclearization and the complete and verifiable denuclearization of the Korean Peninsula and that hasn't changed."

Thursday's talks between the leaders followed Moon's repeated calls for dialogue between the United States and North Korea.

He insists the recent rapprochement between Seoul and Pyongyang may restart six-nation denuclearization negotiations involving the two Koreas, the US, Japan, China and Russia, but that they must be preceded by a resumption of US-North Korea dialogue. The so-called six-party talks have been stalled since late 2008.

Moon, following his meeting with the North's point man on South Korea, Kim Yong-chol, has quoted the North Korean official as saying the communist nation has "enough willingness" to hold bilateral talks with the U.S.

The White House earlier said it will first see if Kim's remarks represented the North's first step toward denuclearization. Trump later said U.S.-North Korea dialogue would only take place under the "right conditions."

In their latest conversation, Moon and Trump agreed to continue closely discussing any progress in future dialogue between the two Koreas, Cheong Wa Dae said.

Moon thanked the US president for sending high-level delegations to the opening and closing ceremonies of the PyeongChang Olympics, led by Vice President Mike Pence and Trump's daughter, Ivanka, respectively.

Trump offered his congratulations for having staged what he called a "very successful" Olympics, it added. (Yonhap)