The priesident said "the presence of nuclear weapons in the Korean peninsula will delay the unification of the two Koreas."
"If unification happens with the presence of nuclear weapons, the neighboring nations won't accept this unification comfortably."
"Many hardships remain, but my resolution for unification will remain solid." "Unification must happen no matter what sacrifice may be needed. It's not the right time to do calculations - unification may bring greater prosperity."
"North Korea must give up nuclear weapons and prosper like China and Vietnam so that the 20 million North Koreans can live with peace and happiness."
Also, regarding the shelling of the Yeonpyoeng Islands, he said: "we stand by our decision to request apology from North Korea. Only when one apologizes for his mishaps one does not repeat the same mistake", demonstrating that the apology from North Korea is the prerequisite for South-North Summit and conversations.
Source : "한반도 핵 있으면 통일 지연될 것