Pyongyang, North Korea -- New Mexico Gov. Bill Richardson provided North Korea with a series of proposals Saturday in what he described as a "good meeting" with the country's chief nuclear negotiator.
Richardson declined to provide details about his proposals, and it was unclear how North Korea responded to them.
Saturday's hour-and-a-half meeting with Kim Gye Gwan, North Korea's chief nuclear negotiator and the man who invited Richardson to North Korea, was the latest stop on a four-day trip aimed at easing tensions in the region.
"Kim Gye Gwan basically told Richardson he didn't sleep last night because of the tensions on the Korean peninsula. It's a very serious situation," said CNN's Wolf Blitzer, who is traveling with the governor in North Korea.
Richardson told Blitzer that he made a series of proposals in the meeting "that he thinks if implemented could ease the crisis, which by all accounts right now is the most serious crisis on the Korean peninsula since the 1953 armistice which ended the Korean war."
Richardson said earlier Saturday he was concerned about escalating tensions on the Korean peninsula, where he is urging "maximum" restraint ahead of scheduled military exercises.
"This is a tinderbox," he told Blitzer. "Right now, my objective is to say -- tamp things down."
Both Koreas have traded tough talk and conducted aggressive military drills in the weeks after North Korea shelled a South Korean island last month.
The tough talk continued Friday as North Korea warned it would launch a military strike against the South if Seoul goes ahead with live-fire drills near Yeonpyeong Island during the next few days, North Korea's state-run KCNA reported.
The South Korean Joint Chiefs of Staff had said that the exercises would take place in the seas southwest of the island between December 18 and 21. But on Saturday the department said the drill would not happen this weekend because of bad weather.
Richardson, a former U.N. ambassador, arrived in North Korea Thursday on a four-day trip he hopes will help to ease tensions in the region.
"Let's cool things down. No response. Let the exercises take place," said Richardson, who added: "On all sides, I'm urging restraint."
He met with a vice minister of North Korea's Ministry of Foreign Affairs on Friday and is scheduled to meet with a top North Korean general Sunday.
"Meeting a top military person is significant," said Richardson, who has hosted a North Korean delegation in New Mexico in the past. "Hopefully, we can keep things from firing up."
Richardson is not in North Korea as an official U.S. envoy.
Tensions mounted between the Koreas on November 23, when North Korea shelled Yeonpyeong Island, which lies in South Korean territory. The attack killed two marines and two civilians and injured 18 people.
The North has accused the South of provoking the attack because shells from a South Korean military drill landed in the North's waters.
Last month's attack was the first direct artillery assault on South Korea since 1953, when an armistice ended fighting.
The U.S. military has said it is concerned that South Korea's scheduled exercises could spark an uncontrollable clash with the North, but the State Department said the exercises are not meant to be threatening or provocative.