"If no one wants another flare-up of hostilities they could publish a declaration ending the war, which is in line with modern trends as well as with the will and wishes of people in the North and South," he said.
Wang Yi maintained that North and South Koreans were one nation and did not want a new war on the peninsula. "We think other countries, including the US, do not want a repeat of hostilities," he added.
North Koreas have been formally at war with the South and the United States after the 1950-1953 conflict. Pyongyang signed an armistice with Washington in 1953, while Seoul refused.
The two Koreas eventually signed a pact in 1992, vowing to refrain from mutual aggression. South Korean President Moon Jae-in met in April with Kim Jong-un of North Korea for a rare summit where they pledged to work actively this year toward reaching a lasting peace.