The United States announced a diplomatic breakthrough with North Korea Wednesday.

Under an agreement reached in direct talks in Beijing last week, North Korea has agreed to allow the return of nuclear inspectors from the International Atomic Energy Agency, and has agreed to implement a moratorium on long-range missile tests, nuclear tests, and nuclear activities at Yongbyon, including uranium enrichment activities, the State Department said. In return, the United States will provide North Korea with a large food aid package.

"To improve the atmosphere for dialogue and demonstrate its commitment to de-nuclearization, the DPRK has agreed to implement a moratorium on long-range missile launches, nuclear tests and nuclear activities at Yongbyon, including uranium enrichment activities," State Department spokeswoman Victoria Nuland said in a press statement Wednesday. "The DPRK has also agreed to the return of IAEA inspectors to verify and monitor the moratorium on uranium enrichment activities at Yongbyon and confirm the disablement of the 5-MW reactor and associated facilities."

Despite the breakthrough, "the United States still has profound concerns regarding North Korean behavior across a wide range of areas," Nuland's statement cautioned. But she added that "today's announcement reflects important, if limited, progress in addressing some of these."

In return, the United States will "move forward with our proposed package of 240,000 metric tons of nutritional assistance along with the intensive monitoring required for the delivery of such assistance," she said.

U.S. envoy on North Korean affairs Glyn Davies last week held the first face-to-face talks with his North Korean counterpart Kim Kye Gwan since the death of North Korean leader Kim Jong-Il in December.

Davies' Feb. 23-24 discussions in Beijing asserted several points, Nuland's statement said. Among them, "the United States reaffirms that it does not have hostile intent toward the DPRK" and that U.S. sanctions are not targeted against the livelihood of the North Korean people.

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Arms control experts welcomed the signs of progress in U.S. efforts to engage Pyongyang. But U.S. North Korea experts and foreign policy hands advised high caution in assessing Pyongyang's intent, given its track record of abrupt reversals.

"These steps are modestly significant," Richard Bush, director of Northeast Asian studies at the Brookings Institution, said in a statement Thursday. However, he noted, they "are only what negotiators call 'confidence-building measures.' They could indeed be an initial step on a path towards serious negotiations ... Or they could simply be a ploy to get nutritional assistance and meddle in South Korean politics. North Korea's record suggests the latter, but we shall see."

While the new agreement "appears to be an important step," Rep. Howard Berman (D-CA), ranking Democrat on the House Foreign Affairs Committee, told Secretary of State Hillary Clinton at a hearing Wednesday, "I'm sure you don't need me to remind you that we've been down this road before, and it remains to be seen whether the North will keep its promises this time."

The return of nuclear inspectors to North Korea for the first time in three years would be a "very positive development," Sen. John Kerry (D-Mass.), chairman of the Senate Foreign Relations panel, said in a statement Wednesday. And he added, the United States has a humanitarian interest in helping the North Korean people receive food aid. "Resuming nutritional assistance to the DPRK is the right thing to do if we can ensure our aid will reach those in need."

The announced measures are "an important step toward a verifiable freeze of the most worrisome North Korean nuclear activities," Daryl Kimball, of the Arms Control Association, wrote in an analysis of the announced agreement. "President Barack Obama and Amb. Glyn Davies ... need to maintain the momentum in the weeks and months ahead."

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