Head of the presidential National Security Office Chung Eui-yong made the remarks while attending President Moon Jae-in's dinner with leaders of the ruling Democratic Party.
According to Democratic Party spokeswoman Kim Hyun, Chung told the audience that North Korea's nuclear and missile threats reach beyond the Korean Peninsula and represent "a challenge to world peace."
Chung was quoted as saying by Kim: "This is an extremely grave situation, as we see a vicious cycle of North Korean provocations and international sanctions.
”The Moon administration inherited the most difficult security environment, but we're doing the best we can."
South Korea has said it is strengthening its ties with its neighbours
Chung also said Seoul is bolstering close coordination with the United States, China, Japan and Russia.
As well, he laid out five basic strands of Seoul's approach to the North Korea issue – denuclearising the Korean Peninsula, bringing peace to the area, taking an active role in resolving the North Korea issue, adopting a two-track approach of seeking dialogue while maintaining pressure on Pyongyang, and delivering a stern response to North Korean provocations.
He also said he "can't imagine" any of the neighbouring powers bypassing Seoul to deal with North Korea.
Chung added: ”The basis of the Moon administration's policy is peaceful denuclearisation of the Korean Peninsula and building peace by improving inter-Korean relations.”
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Mansudae Grand Monument. An enormous bronze statue of President Kim Il Sung and Leader Kim Jong Il, downtown Pyongyang. Image taken the day before Liberation Day where military personnel are visiting the monument to lay flowers for the leaders. Liberation
The comments come ahead of planned joint naval exercises between the US and South Korea which begin on Monday.
Joint military exercises are particularly infuriating to Pyongyang.
The North Korean government views them as a dress rehearsal for an invasion – even as the US insists they are purely defensive in nature.
A report by the Korean Central News Agency (KCNA) listed a string of perceived US provocations – including a litany of bombastic threats from President Trump, recent deployments of a US nuclear submarine and aircraft carrier to the region, and a new round of "high intensity" US and South Korea joint naval drills.
North Korea's leader Kim Jong-un
The article ended with a familiar warning: that the US would be solely responsible for "pushing the situation on the peninsula to the point of explosion."
Ahead of the planned military exercises Pyongyang has revived its threat to launch missiles toward the US territory of Guam.
Kim Kwang Hak, a researcher at the Institute for American Studies of the North Korean Foreign Ministry, is quoted by the news agency as saying: "We have already warned several times that we will take counteractions for self-defence, including a salvo of missiles into waters near the US territory of Guam.
"The US military action hardens our determination that the US should be tamed with fire and lets us take our hand closer to the 'trigger' for taking the toughest countermeasure.”
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