North and South Korea have jointly asked the United Nations to circulate a copy of their leaders' accord concerning peace and security on the Korean Peninsula to all members as an official document, the North's mission said Friday.

They filed the request with U.N. Secretary General Antonio Guterres and General Assembly President Miroslav Lajcak in a letter dated Thursday and signed by North Korea's Acting Ambassador to the United Nations Kim In Ryong and the South's Ambassador Cho Tae Yul. A copy was obtained by Kyodo News.

At their summit on April 27, Kim and Moon issued the Panmunjeom Declaration calling for "complete" denuclearization of the Korean Peninsula and efforts to declare a formal end to the 1950-1953 Korean War.

Asking for official circulation of the landmark declaration "shows the full determination" of both Koreas "to keep advancing the North-South ties without deviation that have entered definitely the new orbit of peace, the orbit of reconciliation and cooperation," a press release from the North's mission said.

"The active support from all U.N. member states to implement the Panmunjom Declaration would exert great encouragement to the dramatic changes towards relaxation of the tension and peace on (the) Korean Peninsula," it also said.

An official from the South Korean mission confirmed that a joint request was made Thursday.

It came after Kim is said to have told a South Korean delegation in Pyongyang that he wishes denuclearization of the Korean Peninsula to take place before U.S. President Donald Trump's first term ends in January 2021.

It was the first time that Kim has given a timeline for denuclearization.

Kim committed to "complete" denuclearization during a historic meeting with Trump in June in Singapore. But negotiations have since stalled as the United States pushes North Korea to make a full account of its nuclear program as a step toward denuclearization.

Pyongyang demands that Washington and other parties first join it in declaring an end to the Korean War, which was stopped with an armistice, not a peace treaty.