The national security advisers of the United States, South Korea and Japan met over the weekend to discuss North Korea and the “complete denuclearisation of the Korean Peninsula,” Reuters reported quoting South Korea’s presidential Blue House.

South Korea’s National Security Office chief, Chung Eui-yong, met U.S. national security adviser H.R. McMaster and Japan’s national security adviser, Shotaro Yachi, to discuss summit meetings between Kim and South Korean President Moon Jae-in, the Blue House in Seoul said.

They also discussed the possible meeting between Trump and Kim, it said.

The security advisers from the three countries talked about the “complete denuclearisation of the Korean Peninsula,” and agreed that “it was important to not repeat the mistakes of the past” and to work together closely, the Blue House said.