(Bloomberg) -- South Korean President Moon Jae-in said Kim Jong Un’s denuclearization pledge “includes everything” -- even giving up his existing arsenal -- but the North Korean leader needed corresponding measures from the U.S. to move forward.

Moon made the remarks Friday in an interview with the BBC ahead of a trip to Europe. The South Korean president, who held his most recent of three summits with Kim last month in Pyongyang, said North Korea was committed to giving up nuclear weapons to achieve economic growth, according to a transcript released by his office.

“He said he would give up nukes for economic development,” Moon said. “It starts with stopping additional nuclear and missile tests, halting the production of nuclear weapons, scrapping facilities that develop missiles and getting rid of the currently existing nuclear weapons and nuclear material. It includes everything.”

How committed Kim is to surrendering a nuclear deterrent that his family spent decades acquiring has been a key area of uncertainty since he initiated talks with Moon and U.S. President Donald Trump earlier this year. A vague agreement signed by Trump and Kim during their historic first meeting in June included an undefined pledge to “work toward complete denuclearization on the Korean Peninsula,” something that could be read as to include U.S. nuclear umbrella over South Korea.

Another point of contention has been Kim’s demands for a declaration ending the Korean War, that was never formally resolved after an armistice was signed in 1953. The U.S. has resisted the request, which could raise questions about American military presence on the peninsula, including the 28,000 troops stationed there.

Moon said that it was “only a matter of time” before such a declaration was agreed to, according to the transcript. He voiced optimism about a second summit between Trump and Kim sometime after the U.S. congressional election in November, saying he hoped the two leaders made a “big decision and agree on a timetable for North Korea’s denuclearization that comes comes with responsive measures from the United States.”

The South Korean president also brushed aside speculation of rift between the two sides. Trump had tersely told reporters Wednesday that Seoul did “nothing without our approval” in response to questions about South Korean discussions about relaxing unilateral sanctions.

“President Trump’s comment is a general statement that we (South Korea) must work closely with the U.S.,” Moon said, adding that South Korea was only preparing for the possibly of building economic ties with its northern neighbor. “Actual economic cooperation would be possible only after sanctions are eased and exemptions are allowed.”

Moon told the BBC that human rights in North Korea could only be improved through inter-Korean exchanges, not international pressure. “The most practical way to improve the North Korean residents’ human rights is through South-North cooperation, and North Korea’s cooperation with the international society, and North Korea becoming a normal country after walking down the road of opening up,” he said.

To contact the reporter on this story: Jihye Lee in Seoul at jlee2352@bloomberg.net

To contact the editors responsible for this story: Brendan Scott at bscott66@bloomberg.net, Peter Pae

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