Diplomats from the United States and North Korea on Friday ended a rare two-day session of talks in New York that Pyongyang’s top representative called “constructive and businesslike.”

The meeting, a preliminary step to explore the reopening of stalled multi-nation talks on North Korea’s nuclear program, yielded no reported breakthroughs and led only to vague promises to stay in touch. The ambiguous outcome doubled as a reminder that many tentative steps will likely be necessary before the Obama administration and its allies push again for six-party talks, which have not been held since late 2008.

North Korean vice foreign minister Kim Kye Gwan met for about three hours Friday with Ambassador Stephen Bosworth, the top U.S. envoy for North Korean affairs. Kim told reporters in New York he hoped for continued talks. Bosworth said future talks can happen “if North Korea demonstrates through its actions that it supports the resumption of the six-party process as a committed and constructive partner.”

The six-party process faces skepticism from almost all involved — the result of years of denuclearization promises from Pyongyang and subsequent efforts to build its nuclear arsenal. The isolated authoritarian country, many security analysts say, depends on its nuclear threat for legitimacy.

The State Department described this week’s talks as a means for gauging North Korea’s willingness to fulfill a 2005 agreement to abandon its nuclear program. Since that agreement was reached — with the promise of North Korea receiving aid and energy in return — Pyongyang has twice tested nuclear weapons; it also has built up a uranium enrichment program, unveiled late last year to a visiting American scientist.

As leader Kim Jong Il tries to pass power to his youngest son, Kim Jong Eun, North Korea has become among the Obama administration’s most puzzling targets: Diplomacy gives the United States a chance to influence Pyongyang and keep its nuclear program from further expansion. But diplomacy also threatens a repeat of past embarrassments, with Pyongyang making agreements and then ignoring them.

That’s why both the United States and South Korea have been so cautious about returning to the six-party talks, with officials in Washington and Seoul emphasizing that Pyongyang must meet certain “pre-steps” in advance of the multi-nation talks. Those pre-steps have been left largely undefined, but on Friday, South Korean nuclear envoy Wi Sung-lac, the chief negotiator with North Korea, said Pyongyang must cease its nuclear activities and allow International Atomic Energy Agency inspectors back into the country.

“It’s a huge task to achieve,” Wi said during a lunch with several foreign reporters, “but a comprehensive approach is better than quick deals. It has to be a concrete road map.”

One U.S. expert, speaking on the condition of anonymity to freely share his opinion, said that the pre-steps outlined by Wi set too high a bar. North Korea, he said, will want to save the major concessions on its uranium enrichment program until after the six-party talks resume.The talks were last held in December 2008, but they officially fell apart in April 2009 when North Korea tested a missile and walked out of the talks in response to international condemnation. The Thursday and Friday meetings in New York marked the first high-level discussions between the two nations in 18 months.

“These were exploratory talks,” State Department spokesman Mark Toner said. “We were clear-eyed going into them. And I think we’re going to assess — we’re going to consult with our partners, certainly South Korea but also our other six-party talk partners, and I think we’ll assess next steps following these meetings.”

Special correspondent Yoonjung Seo, in Seoul, contributed to this report.