President Yoon Suk Yeol on Thursday has departed to attend the first standalone trilateral summit with US and Japanese leaders, a high-profile gathering widely expected to formalize a new three-way cooperation on security and economy to deter the growing aggression from North Korea and to brace for economic uncertainty.

At the US presidential retreat Camp David, the leaders are set to adopt the "Camp David Principles" and the "Spirit of Camp David," documents laying out the main principles for collaboration between the three nations and to institutionalize their partnership.

Agreements on holding presidential meetings as well as trilateral military exercises annually are expected to be included in the documents. Data sharing on North Korean ballistic missile threats and setting up a hotline among the three leaders are also expected to be on the agenda.

Hours before leaving Seoul, Deputy Security Director Kim Tae-hyo told reporters that the three leaders would adopt the two documents and are reviewing to adopt one more. He did not elaborate on the third document.

The Camp David Principles are documents that imply the main principles of trilateral cooperation between South Korea, the US and Japan.

“The leaders of the three countries of Korea, the United States and Japan will state the principle of strengthening cooperation for peace and prosperity in the Asian region, including the Korean Peninsula, the Association of Southeast Asian Nations, Pacific Island countries and around the world, based on common values ​​and norms,” he said.

“We will also jointly respond to global issues such as economic norms, advanced technology, climate change development and (nuclear) non-proliferation,” Kim said.

The Spirit of Camp David is a joint statement containing the joint vision of the three leaders and the major results of the summit. It contains a vision of trilateral cooperation and the will to put it into practice.

“In the face of complex crises such as intensifying geopolitical competition, the war in Ukraine, climate crisis and nuclear proliferation, the leaders of the three countries agreed on the inevitability of Korea-US-Japan cooperation and came to announce a new era for the trilateral partnership,” Kim said.

The joint statement addresses the creation of a concrete consultative body, a common vision that includes ASEAN and Pacific Island countries, regional threats, Ukraine-related issues, extended deterrence, joint drills, economic cooperation and economic security.

Yoon will arrive in the US in the late afternoon on Thursday (US time) and travel to Camp David in Maryland the following day. On Friday, Yoon will participate in bilateral and trilateral summits throughout the day before leaving for Seoul in the evening.

The three leaders will hold a joint press conference after the summit.

When asked whether the issue of contaminated water in Fukushima could be included on the agenda at the Korea-Japan summit, an official from the Korean presidential office said: "We decided not to discuss the issue of contaminated water at the bilateral meeting between Korea and Japan."

A day earlier, White House spokesperson John Kirby said in a press briefing that the three countries will announce significant initiatives on Friday, which will help “cement our trilateral cooperation going forward.”

“These initiatives will take our trilateral relationship to new heights as we work together to deliver benefits for our people and for people across the region,” he said.

Park Won-gon, a professor in the department of North Korean studies at Ewha Womans University, said the most important thing is how institutionalized Korea-US-Japan cooperation will be and whether the declaration of an annual summit will be stipulated. “When it is written, although it is not binding, it will be difficult for the next administration to make changes,” he said.

Another aspect to pay attention to is the extent to which the statements will talk about China, as keeping China in check is a core agenda item for the US, Park said. China has expressed discomfort about the growing solidarity between the three nations, describing it as part of the US’ agenda to build a “mini-NATO-style” trilateral military alliance in Northeast Asia.

When asked whether China’s threats to Taiwan would be on the agenda, Kirby said he did not want to get ahead of the discussions too much. “There’s been no change to American policy when it comes to the ‘One China’ policy,” he said.

Regarding the possibility of North Korea carrying out an armed provocation during the Korea-US-Japan summit and the Ulchi Freedom Shield exercise, a high-ranking official from the Korean presidential office said on the condition of anonymity, "South Korea and the US are strengthening their readiness posture before and after this visit, and military exercises are also underway between the two countries. We will leave with a response manual and preparedness as we did in several overseas visits.”