UNITED NATIONS >> The U.N. political chief said today that senior North Korea officials told him during a four-day visit to the country last week “that it was important to prevent war” over the country’s rapidly advancing nuclear and ballistic missile programs.

Jeffrey Feltman told reporters after briefing the U.N. Security Council privately that “how we do that” was the topic of more than 15 hours of discussions he had with Foreign Minister Ri Yong Ho, Vice Minister Pak Myong Guk, and other officials.

Feltman, a veteran American diplomat who is the U.N. undersecretary-general for political affairs, said he told the North Koreans “they need to signal that they’re willing now to go in a different direction, to start some kind of engagement, to start talking about talks.”

He called the mission the most important one that he has ever taken, but he was cautious about the impact and future steps.

“They listened seriously to our arguments … they argued with us,” Feltman said. “They did not offer any type of commitment to us at that point. They have to reflect on what we said with their own leadership” and decide how to respond.

“I think we’ve left the door ajar, and I fervently hope that the door to a negotiated solution will now be opened wide,” he added.

Feltman’s visit came at a time of heightened tensions between North Korea and South Korea, Japan and the United States, sparked by the reclusive country’s frequent missile launches and recent nuclear test explosion, and particularly by its latest launch of a long-range ballistic missile that experts say could reach Washington.

Kim and U.S. President Donald Trump have traded insults and engaged in escalating rhetoric in recent months but Secretary of State Rex Tillerson softened the U.S. stance on possible talks with North Korea today.

Tillerson offered to meet the North Koreans without preconditions and said it was it “unrealistic” to expect the nuclear-armed country to come to the table ready to give up a nuclear weapons program that it invested so much in developing. He said Trump endorsed his stance.

Feltman, when asked about the new U.S. approach, said the Security Council is united on the need for a political solution, “so I would underscore that that was the message I took to Pyongyang.”

“But we have to get there by opening the door to a different direction from the current trajectory” with North Korea, he said. “They agreed that it was important to prevent war.”