WASHINGTON — North Korea will halt long-range missile launches and nuclear weapons tests and suspend the enrichment of uranium at its key nuclear site in exchange for badly needed food aid from the United States, the two countries announced Wednesday.

The surprise deal, reached in talks last week in Beijing, appeared to raise the prospects of resuming long-stalled negotiations on shuttering North Korea's nuclear weapons program, although there was considerable skepticism that Pyongyang, which has hailed the nuclear effort as its greatest achievement, will fulfill its end of the bargain.

Secretary of State Hillary Clinton called the accord a "modest first step." White House spokesman Jay Carney said that further progress would "depend on actions the North Koreans take to demonstrate that they are upholding the commitments they've made."

If implemented, the deal would represent a major policy shift by North Korea after the death of dictator Kim Jong Il from a heart attack in December and the accession of his son, Kim Jong Un. North Korea has refused to suspend its nuclear program since six-nation talks over the issue collapsed nearly four years ago.

The talks in Beijing, which took place during a 100-day mourning period for Kim Jong Il, were held with the same North Korean officials who've been involved in the nuclear negotiations for years, said a senior Obama administration official who briefed reporters on the condition of anonymity as a matter of policy.

"It shows that they are interested with some alacrity to reach out, to get back to the table, and begin to try to make diplomatic progress, and I think that's a positive sign," he said.

Under the deal, U.N. International Atomic Energy Agency inspectors will return to the Yongbyon nuclear complex to monitor compliance with the enrichment suspension, as well as the disabling of a 5-MW reactor and related facilities, State Department spokeswoman Victoria Nuland said.

Enrichment is the process that produces — depending on the duration — low-enriched uranium fuel for power reactors and highly enriched uranium for nuclear weapons. Pyongyang will have to contact the IAEA to make arrangements for the deployment of the monitors, the senior Obama administration official said, adding that the speed with which it does this will be viewed as an indication of its commitment to the deal.

The agreement gives President Barack Obama a boost just weeks before he joins some 50 other heads of state in South Korea to review progress on his initiative to lock up the world's nuclear weapons materials by the end of 2014, keeping them safe from theft. It also comes as his administration grapples with the growing crisis over Iran's refusal to halt its uranium enrichment program, which the U.S. and other countries contend is part of a secret effort to develop nuclear weapons — a charge Tehran denies.

The accord with Pyongyang, however, carries potential political risks for Obama as he steps up his re-election campaign. The North Koreans have a history of reneging on agreements involving their nuclear program, something Republicans lost no time in recalling, and that GOP presidential candidates could use to bash the president.

"Today's North Korea announcement ... sounds a lot like the failed agreements of the past," Rep. Ileana Ros-Lehtinen, R-Fla., the chairwoman of the House of Representatives Foreign Affairs Committee, told Clinton at a hearing on the State Department budget. "We've bought this bridge several times before."