Senior South Korean and US officials have been holding a flurry of meetings in Washington in the run-up to a summit between their respective leaders Moon Jae-in and Donald Trump next week.

South Korean Foreign Minister Kang Kyung-wha returned home after meeting US Secretary of State Mike Pompeo -- their first meeting since the second summit between Trump and North Korean leader Kim Jong-un collapsed in February.

The top diplomats’ discussions were followed by a meeting between Kim Hyun-chong, the second deputy chief of the South Korean National Security Office, and US deputy national security adviser Charles Kupperman. South Korean Defense Minister Jeong Kyeong-doo also met acting US Secretary of Defense Patrick Shanahan.

Besides their counterparts, the visiting South Korean top diplomats and security officials had discussions with other senior US officials and members of the US Congress. All the activities are part of the Moon government’s efforts to put the stalled US-North Korea disarmament talks back on track.

Moon, who will fly to Washington next week to discuss North Korea with Trump, said Monday that his US trip is the outcome of joint South Korean and US efforts to revive momentum for talks at an early date. The summit reflects the South Korean government’s consistent, determined pursuit of the Korean peace process and President Trump’s firm commitment to US-North Korea negotiation, Moon said.

Indeed, the South Korean leader, who held three summits with Kim last year, is in a good position to mediate between Trump and Kim. It is almost certain that Moon’s aides have been communicating with their counterparts in Pyongyang since the Hanoi talks and will do so after Moon returns home.

There is also possibility that either Moon and Kim will meet at the truce village of Panmunjom -- as they did twice last year -- or Kim will keep his promise to visit Seoul, which he made when Moon visited Pyongyang in September.

By any means, it is desirable for Moon to try to revive the US-North Korea talks. What’s positive is that the US president has provided a good environment for a resumption of negotiations with North Korea.

Trump, who had rebuffed Kim’s calls to ease sanctions imposed in response to North Korea’s nuclear and missile provocations in their Hanoi talks, publicly ruled out additional sanctions against the North.

He even noted that North Koreans are “suffering greatly.” He reaffirmed that he has a very good relationship with Kim and they understand each other.

For its part, North Korea is also manifesting no hostilities against the US, which provides grounds for Moon to get Kim back to the negotiation table with the US president for what South Korean officials say will and should be a “top-down” settlement of the nuclear issue.

That will be no easy task, however. The biggest problem is that the US and North Korea are wide apart on what each side wants the other side to do first.

Recent US news reports disclosed that in Hanoi, Trump demanded North Korea hand over all of its nuclear weapons and materials. The US also listed the North’s chemical and biological weapons, according to the reports.

While the hardening of the US position definitely is a welcome development from the perspective of the international community that needs to remove the North Korean nuclear threat once and for all, it would definitely make negotiations with the North tougher. Remember that Kim offered in Hanoi only the dismantling of some outdated facilities in Yongbyon and demanded sanctions relief.

The North Korean position is bolstering the already strong US and international skepticism about Kim’s commitment to denuclearization. Moon’s first mission, therefore, should be -- based on unity with Trump -- working out effective measures to persuade -- or pressure, if necessary -- Kim to move on substantial disarmament process.

Moon said the three parties -- the two Koreas and the US -- cannot and will not turn back to the past in which the North’s denuclearization endured twists and turns. It is needless to say who should change in order not to repeat the past.