South Korean President Moon Jae-in has said North Korean leader Kim Jong un reaffirmed his commitment to “complete” Denuclearisation of the Korean peninsula and to a planned meeting with U.S. President Donald Trump.

At a news conference in Seoul a surprise meeting with North Korean leader Kim Jong Un in the truce village of Panmunjom the South Korean President said they have agreed that a possible North Korea-U.S. summit must be held successfully.

South Korea’s Moon, who returned to Seoul on Thursday after meeting trump in Washington in a bid to keep the high-stakes U.S.-North Korea summit on track, said he delivered a message of trump’s “firm will” to end the hostile relationship with North Korea and pursue bilateral economic cooperation.

The meeting was the latest dramatic turn in a week of diplomatic ups and downs surrounding the prospects for an unprecedented summit between the United States and North Korea, and the strongest sign yet that the two Korean leaders are trying to keep the on-again off-again meeting on track.