For the first time in his seven years in office, President Bush will have a South Korean counterpart with similar views on North Korean nuclear disarmament when Lee Myung-bak is inaugurated Monday.

It may already be too late for them to move forward on an agreement to rid the North of its nuclear weapons.

Seoul's change in leadership comes with six-nation nuclear negotiations at an impasse. It will take time for Lee to set up a new North Korea policy, and Bush, with less than a year left in his presidency, has little time to negotiate.

Lee's stance may also turn out to be even tougher than Bush's now that the United States is pressing hard for an agreement.

That would be an odd turn of events given that the Bush administration has for years seen South Korea as too eager to engage the North. The outgoing president, Roh Moo-hyun, who was elected on an anti-American platform, favored a policy that provided aid without demanding concessions from North Korea.

Lee has pledged to tie South Korean aid to the North to progress in disarmament talks. He also has suggested he will address North Korean human rights abuses, which the previous two South Korean presidents shied away from.

That has pleased conservatives in the United States who have been critical of Roh.

Rep. Ed Royce, R-Calif., said in an interview that Lee "has spoken of a pragmatic demand for reciprocity in engaging Pyongyang, and I think insisting on reciprocity and transparency was supposed to be what the six-party talks were all about."

On Saturday, Lee named a university professor and North Korean critic as unification minister in charge of relations with the North.

Lee begins his five-year term as nuclear talks face a deadlock. Envoys are pushing the North to hand over a complete declaration of its nuclear programs, which it had promised to do by the end of last year. Washington has refused to take the North off a U.S. terrorism blacklist, a coveted goal of North Korean leader Kim Jong Il, until negotiators have the declaration.

In recent remarks, the incoming South Korean president has indicated a slow approach. He said that "although the dismantlement process is currently being delayed, we remain patient and mindful of the need to proceed carefully."

Such caution could create tension between the U.S. and South Korean governments as the Bush administration presses for an agreement.

"They need action; they need progress," Jack Pritchard, the State Department's chief North Korea expert until 2003, said about the U.S. administration.

The danger is that the United States, if it sees little progress as 2008 comes to a close, could become "so frustrated that, regardless of what the relationship is with Lee Myung-bak," it will act in the negotiations in ways that might not be compatible with Lee's aims, Pritchard said at the American Enterprise Institute.

The United States took a hard-line approach on North Korea early in Bush's administration, with Bush including the North in an "axis of evil" with Iran and deposed President Saddam Hussein's Iraq.

Following North Korea's test of a nuclear device in 2006, however, U.S. diplomats have pushed to settle a nuclear deal with Pyongyang. Bush himself sent a letter in December to North Korean leader Kim.