"Through denuclearization on the Korean Peninsula, the South (Korea) and the North (DPRK) can foster a new era of cooperation," he said. "The road towards peaceful unification is one that can be guaranteed by peace through co-existence."

At a news conference in Seoul's Press Center, Lee said his administration will persuade the Democratic People's Republic of Korea (DPRK) to denuclearize within the framework of the six-party talks and boost the US-DPRK dialogue.

Lee, who won presidential election by landslide on Wednesday, said "I pledge before you to open an 'era of peace on the Korean Peninsula without nuclear weapons'."

Lee will take office on Feb. 25 next year.