South Korea's top diplomat said Monday her government aims to formally end the Korean War by the end of this year and that the leaders of North Korea and the United States have discussed the issue.

Foreign Minister Kang Kyung-wha stressed, however, South Korea is flexible on the specific timing and format of the envisioned, largely symbolic declaration.

"(We) are in close consultations with the US on this field. And I know that there was (relevant) discussion at the North Korea-US summit level," she said at a press conference to mark the first anniversary of her inauguration.

President Donald Trump held bilateral talks with the North's leader Kim Jong-un in Singapore last week. They produced a four-point joint statement on denuclearization and improved relations between the two sides that had fought each other in the 1950-53 Korean War. But the agreement did not address ending the war.

The conflict finished in an armistice agreement, not a peace treaty.

Kang described officially ending the war as the "entrance" to a process to establish a peace regime on the peninsula.

"I think China could play a very important role in the overall process, and South Korea will have close consultations with China," she said.

The South's liberal Moon Jae-in administration apparently hopes to have a ceremony to terminate the war at the border village of Panmunjom on July 27, the armistice agreement anniversary.

But the minister said the government won't be obsessed with a timeline or format.

South Korea will closely monitor the expected high-level talks between the North and the US to follow up on the Singapore accord.

Secretary of State Mike Pompeo was quoted as telling Kang that he will push for the negotiations "quite fast." They had a phone conversation earlier in the day, during which they reaffirmed the importance of the allies maintaining close coordination on next steps.

Seoul and Washington share the view that sanctions on the communist nation should remain in place until it takes "substantive" denuclearization measures, according to the minister.

She expressed hope that she will hold separate talks with her North Korean counterpart, Ri Yong-ho, on the sidelines of the ASEAN Regional Forum, which will take place in Singapore in early August.

On the proposed "hotline" between Trump and Kim, meanwhile, Kang said it does not appear imminent.

Pompeo said there's no concrete action yet on the matter, according to the minister.

Trump publicly said last week that he gave his "very direct number" to Kim.

"I can now call him," he said. "I gave him a very direct number. He can now call me if he has any difficulty. We have communication."

Trump earlier presented a standard for the first-stage goal of the denuclearization process, although the South's foreign minister would not clearly agree on the point.

"There will be a point at which, when you're 20 percent through (the denuclearization process), that you (North Korea) can't go back," he said. "When you hit a certain point you can't go back."

Kang said it's a matter to be further discussed by experts. (Yonhap)