The top nuclear negotiators of South Korea and the US on Tuesday reaffirmed their commitment to sustaining the North Korea policy toward denuclearization despite the political transitions in both countries.

Kim Hong-kyun, special representative for Korean Peninsular peace and security affairs at Seoul’s Foreign Ministry, hosted his US and Japanese counterparts, Joseph Yun and Kenji Kanasugi, to review new sanctions adopted at the UN and by the three nations.

The three-way meeting came about a month ahead of the inauguration of Donald Trump as the new US president, who has expressed his willingness to meet North Korean leader Kim Jong-un. The president-elect on Tuesday picked ExxonMobil Chief Executive Rex Tillerson, who has no foreign policy experience, as secretary of state, while threatening to jolt Washington’s decadeslong support of the “One China” policy.

Seoul, meanwhile, is undergoing a political upheaval. With the parliament’s impeachment of President Park Geun-hye last Friday, the nation is awaiting the Constitutional Court’s decision that will determine the fate of her presidency, and the timing of the next presidential election.

While acknowledging the changing circumstances, the envoys downplayed their impact on the three countries’ united front against Pyongyang, vowing to continue ramping up pressure and sanctions until the Kim regime changes course.

“There is, to be frank with you, an important domestic transition going on both in Washington and Seoul. I’m sure like everyone else, North Koreans are watching these transitions carefully,” said Yun, special representative for North Korean policy at the US State Department.

“It is also an opportunity for them to see what can be done for the ultimate goal of peaceful denuclearization. But so far we have not seen any signs that they want to engage in a meaningful way, so it’s very important for us to impose costs on their behavior.”

The new ambassador said he was “confident” the incoming Trump administration would not change the US’ approach toward North Korea’s nuclear program, which he said had always garnered bipartisan support.

“When a new administration or a new government takes power, it’s always going to take a fresh look,” Yun said.

“Essentially, I would say the North Korean nuclear issues have always been a bipartisan issue. Nobody, whether they are republicans or democrats, has said anything but the goal of denuclearization.”

The three officials also emphasized the need for “good implementation” of the new UN Security Council resolution, which is intended to slash the regime’s coal exports to China by nearly 60 percent or $700 million.

Over the weekend, Beijing’s commerce ministry imposed a freeze on North Korean coal imports, which were nearing the UN-set annual quota. But skeptics have raised concerns about the relative opacity -- or possible manipulation -- of official Chinese data.

Kim Hong-kyun, who met with his Chinese counterpart Wu Dawei last week, pledged to boost “strategic communications and cooperation” with Beijing and Moscow, calling for them to play a “constructive role” in intensifying pressure on the unruly regime.

“2017 will likely be a watershed year for the North Korean nuclear issue,” he said.

“North Korea is rolling back the clock of history through nuclear blackmail against the whole international community. We warn that if it does not give up its nuclear ambition, the North will end up taking the path toward self-destruction and that denuclearization is the only choice it has.”

By Shin Hyon-hee (heeshin@heraldcorp.com)