The United States has resumed contact with North Korea (search) but the talks at a security conference in New York have not produced a decision to reopen negotiations on Pyongyang's nuclear weapons program, the State Department said Friday.

The same two American diplomats who met secretly in May with North Korean counterparts in New York, State Department envoy Joseph DiTrani and James Foster, were involved, spokesman Sean McCormack said. Foster is in charge of the department's office of Korean affairs.

He described it as a "contact" and said there was no negotiating between the two sides at the conference held by the National Committee on American Foreign Policy.

The conference dealt primarily with the Korean peninsula, and customarily at such events "there is a natural exchange among the attendees," McCormack said.

"I am not going to characterize it beyond that," the U.S. official said, but added: "We are still waiting to hear from North Korea a date when they will return to the six-party talks (search) and engage in those talks in a constructive manner."

After the May meeting surfaced, McCormack said North Korea had registered an interest in reopening the negotiations, last held a year ago. No date or location has been set since, and McCormack declined to say whether the North Koreans had expressed interest again in the latest encounter.

"What matters is that they return to the talks and engage in a constructive manner," he said.

China, Russia, South Korea and Japan are aligned with the United States in the negotiations, trying to persuade North Korea to halt a nuclear weapons (search) program that U.S. intelligence is convinced already has produced at least two bombs.

Last week, Undersecretary of State Robert Joseph suggested that China put economic pressure on North Korea to induce it to reopen nuclear weapons negotiations.

Joseph, who has succeeded John R. Bolton as the department's top arms control official, said, "We think China can do more to get them to eliminate their nuclear weapons program."

China shares with the United States and other nations an interest in a nuclear-free Korean peninsula, Joseph said. "It is very much in China's interest to exert as much influence as it can," he said.

"My sense is that the North Koreans will come back," he said. "I hope in the near term."