North Korea's top diplomat Ri Su Yong proposed a reunification under a confederation system in the first UNGA speech of a Pyongyang foreign minister in 15 years.

While addressing the United Nations General Assembly (UNGA) late on Saturday, Ri stressed reunification was "the main goal" of his country and "the biggest desire of the whole nation", according to ITAR-TASS and DPA.

The minister, however, described South Korea's current proposals as "unrealistic", making it clear a confederation where the Pyongyang regime and the Seoul government could coexist was the only viable option.

In Ri's words, such a confederation was the only way to prevent a war and promote peace.

The Wall Street Journal quotes him as saying his the nuclear program implemented by his government is not "a bargaining chip".

After his speech North Korea's Foreign Minister met UN Secretary General Ban Ki-Moon, who was formerly the South Korean top diplomat.

Speculations are growing over the past days about the health of North Korean leader Kim Jong-Un, with state TV station revealing on Friday "he is not feeling well" just days after he failed to arrive at a key regime meeting. He had also been away from public view for an unusually long stretch of time.