SEOUL, South Korea (CNN) -- President-elect Lee Myung-bak said Thursday he would not shy away from criticizing North Korea's authoritarian regime, the day after his landslide win ended a decade of liberal rule that has fostered unprecedented reconciliation on the divided peninsula, The Associated Press reported.
South Korean presidential candidate Lee Myung-Bak and his wife cast their ballots in Seoul on Wednesday.
"I think unconditionally avoiding criticism of North Korea would not be appropriate," Lee told a news conference. "If we try to point out North Korea's shortcomings, with affection, I think that would go a long way toward improving North Korean society, " AP reported.
The victory by Lee of the conservative Grand National Party marks a shift to the right in Seoul after a decade of liberal presidents -- who pursued a "sunshine" policy of engaging the North and largely refrained from criticism of its human rights record, AP reported.
Lee pledged to work for a nuclear-free Korean peninsula and strengthen Seoul's alliance with the United States. "The most important thing is for North Korea to get rid of its nuclear weapons," he said, AP reported.
"The North's abandonment of its nuclear programs is the way for the North to develop" its economy, Lee said. He said the divided Koreas can open a new era of cooperation through demilitarization. He also told reporters he will press North Korea to improve its human rights record, AP reported.
Lee, a former Seoul mayor and Hyundai executive currently facing investigation amid allegations of fraud, will take office in February.
Lee's main rival was Chung Dong-Young of the United New Democratic Party.
Chung, 54, a former television news anchor and unification minister, earlier told reporters he "humbly accepted the people's choice. I hope [president]-elect Lee Myung-bak will do a good job for the country."
Third-placed independent candidate Lee Hoi-Chang also congratulated Lee.
Supporters gathered outside the Grand National Party headquarters in Seoul broke into cheers as television stations started to report news of Lee's victory.
Lee, 66, broke from the pack of candidates by virtue of his rags-to-riches life story and his business background.
He had collected trash to put himself through college, then rose to become one of the youngest CEO's of Hyundai Construction, earning himself the nickname "The Bulldozer." Watch why Lee has the upper hand among voters »
The frontrunner throughout the campaign, Lee promised economic reform aimed at raising annual growth to seven percent per year and establishing South Korea among the world's top seven economies.
But the election was thrown into uncertainty Monday when the National Assembly voted to investigate accusations of fraud against him after political opponents released a video clip of him saying he founded an investment company at the center of stock manipulation charges.
Lee will take over from Roh Moo-hun, who had promised reform and clean governance. But scandal has marred his five-year term, with a string of Cabinet officials forced to resign over corruption allegations and Roh himself surviving an impeachment attempt in 2004.
Critics have also challenged Roh's economic policies, saying he raised taxes, created higher unemployment and caused real estate prices to soar.
At the same time, he improved relations with North Korea and became only the second South Korean president to meet with his counterpart in the North.
Roh offered his congratulations to Lee on Wednesday. "We respect the people's choice shown in this election," presidential spokesman Chen Ho-se on said in a statement, AP reported. Lee is to take office in February. E-mail to a friend
CNN's Seoul Bureau Chief Sohn Jie-Ae contributed to this report.
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