Pyongyang, North Korea (CNN) -- New Mexico Gov. Bill Richardson said Friday that he had made some progress after wrapping up his first meeting with a North Korean government official.
Richardson, a former U.N. ambassador, arrived in North Korea Thursday on a four-day visit that he said will help ease tensions in the region.
Richardson met with a vice minister of North Korea's' Ministry of Foreign Affairs on Friday. He will meet with North Korea's senior nuclear negotiator Kim Gye Gwan on Saturday.
Richardson has said he hopes "to bring down the temperature in the Korean peninsula" during his trip.
Both Koreas have traded tough talk and conducted aggressive military drills in the weeks after North Korea shelled a South Korean island last month.
And 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 over the next five days, North Korea's state-run KCNA reported.
South Korea "should take a prompt measure to stop the planned provocative maritime shelling from Yeonpyeong Island," the report said. The Korean People's Army "will deal the second and third unpredictable self-defensive blow at them to protect the inviolable territorial waters of" North Korea "as it had declared before the world."
Other interested countries are getting involved in diplomatic wrangling. The Russian Foreign Ministry published a statement on its website, calling for South Korea "to refrain from conducting its planned live-fire artillery exercises "in order to prevent any further escalation of tensions on the Korean peninsula."
Richardson has said he will try to get "North Koreans to curtail their aggressive behavior, to see if there is some basis for negotiations, to get them to stop the uranium enrichment."
Richardson, who has hosted a North Korean delegation in New Mexico in the past, said he hopes his past relationships will help.
The meetings are coming at a very pivotal time.
Tensions are "the highest I've ever seen. I've been involved with North Korea for the last 10 to 15 years," Richardson said. "I can't remember when the tension were as high as it is now. And you worry about some kind of action hastening a potential war. And we have to avoid that at all costs."
CNN's "The Situation Room" Anchor Wolf Blitzer contributed to this report.