US and North Korean officials have reportedly been hashing out terms of the agreement through back channels led by CIA Director Mike Pompeo - Trump's nominee to replace Secretary of State Rex Tillerson.
"Even if we were aware of the talks, we can not comment on it", said an anonymous Cheong Wad Dae official, according to Yonhap News Agency.
The back-channel talks are the latest move in a flurry of diplomatic activity aimed at resolving the nuclear crisis on the Korean peninsula. North Korea had relayed that proposal to the United States, according Japanese newspaper Asahi Shimbun.
Mr Pompeo is now awaiting confirmation as secretary of state in the coming weeks.
"The U.S. has confirmed that Kim Jong Un is willing to discuss the denuclearization of the Korean Peninsula", said a second U.S. official.
The preparations for the Trump-Kim summit are reported to be made through the channel that runs between the Central Intelligence Agency and the Reconnaissance General Bureau.
She said the U.S.is deeply concerned about the state of North Korean citizens' well-being.
"It's a natural step in the right direction".
"But we can not say for certain that the U.S. counterpart in the North was Reconnaissance General Bureau". However, he added that it does not make a positive outcome more likely.
China and Russian Federation are both permanent members of the United Nations Security Council, which has imposed sanctions on North Korea in a bid to force negotiations with Pyongyang.
South Korea's president, Moon Jae-in, is due to meet Mr Kim in the joint security area of Panmunjom on April 27th for what will be only the third summit between the two Koreas since the peninsula was divided at the end of the Korean War (1950-53).
According to the report, American officials are said to have spoken several times with their North Korean counterparts, and even met up with them up to three times to discuss preparations.
The Mongolian capital Ulaanbaatar has also been raised as a possible location, the officials told CNN.