SEOUL, South Korea — Secretary of State Condoleezza Rice scored a major victory this week when North Korea agreed to return to international negotiations on dismantling its nuclear-weapons programs.

After nearly three years of wrangling in Washington over strategy, Rice has steered the Bush administration much closer to the course that South Korean President Roh Moo-hyun and other critics have been urging for more than two years: meeting directly with the North Koreans and offering them tangible incentives, including energy assistance, security guarantees and humanitarian aid, if they renounce their nuclear-weapons programs.

"The United States has been listening to the South Koreans, the Chinese, the Russians," said Moon Chung In, a South Korean academic with close ties to Roh's government. "Maybe they are not changing their fundamental position, but there has been a clear change in tactics. We can believe now that President Bush is truly interested in a peaceful solution."

Rice insisted this week that there has been no change in U.S. policy: Isolate North Korea, refuse to reward it for bad behavior, and make clear that it can get the benefits it seeks only by negotiating with the United States, China, Japan, South Korea and Russia in six-nation talks.

But yesterday, she praised as "a very creative idea" South Korea's new offer to send 2 million kilowatts of electricity across the demilitarized zone to energy-starved North Korea if it commits to denuclearization. That offer seemed to have cinched the deal for the North to return to talks.

A senior aide who briefed reporters on Rice's plane yesterday after her six-day trip to Asia said the United States has known about the energy proposal "for some time," although he would not say exactly how long. The South Korean unification minister presented the offer to North Korean leader Kim Jong Il on June 17, and Kim reportedly told him that he was prepared to give up his nuclear-weapons programs.

In North Korea yesterday, Kim told a visiting Chinese diplomat that his country seeks a nuclear-free Korean Peninsula, and he hoped the new round of talks the last week of July would help reach that goal. The United States, Russia, Japan, China and North and South Korea will meet in Beijing and attempt to craft a disarmament strategy.

Standing with Rice beside him, South Korea's foreign minister said yesterday that South Korea had sought with its energy offer to break the yearlong "stalemate" in the six-party talks, which North Korea had been boycotting since June 2004.

The Rice aide said that in recent months, the United States and its allies have worked to put into place many pieces of a package that could lure North Korea back to the bargaining table.

North Korea has long sought a written security guarantee from the United States, which the Bush administration has refused. But administration officials have pledged, publicly and in a private meeting with North Korean diplomats in New York, that the United States has no intention of attacking or invading North Korea.

In a speech in March in Tokyo, Rice also said that the United States recognized North Korea as a sovereign state, another key issue for the Kim regime.

Not so long ago, President Bush called the North Korean leader a "tyrant." Vice President Dick Cheney labeled him "one of the world's most irresponsible leaders." Rice declared his regime an "outpost of tyranny."

But in early June, when the Bush administration began receiving signals that North Korea was prepared to return to the bargaining table, the language from the White House purposefully turned more polite.

On at least two occasions, the president suddenly referred to the communist leader with a title of respect: "Mr. Kim Jong Il."

"To Americans, this seems like an absurd kind of thing," the Rice aide said, "but it matters to the North Koreans."

Another important move came last month, when the United States announced it would give the impoverished North Koreans 50,000 tons of food, without — as the aide put it — any attempts "to make them jump through nuclear hoops" to get it.

After North Korea's announcement that it would return to the talks, South Korea also said it would send the North a large food shipment.

In recent months, there have been several U.S.-North Korean meetings in New York, including the one at which U.S. diplomats pledged that the United States had no intent to attack. And Saturday, U.S. Assistant Secretary of State Christopher Hill had a three-hour dinner with the head of the North Korean delegation to the six-party talks, Kim Gwe Gwan. They agreed on the week of July 25 to resume talks.