The presidential office has denied media reports that President Moon Jae-in's special envoys will discuss the release of American detainees in North Korea during their trip to Pyongyang.

A senior presidential official told reporters on Monday that it's hard to say with 100 percent certainty that the issue will not be discussed, but that it’s not the theme of the trip.

The official added that the denuclearization of the North is the key point of preliminary talks between the U.S. and North Korea.

Some media outlets quoted a ruling party official as saying that the special envoys will discuss ways to release three American citizens detained in the North and facilitate and induce U.S.-North Korea dialogue.

The presidential official also said that the two Koreas have reached a general agreement about when the delegation will meet with North Korean leader Kim Jong-un during the trip, but refused to elaborate on the details.