Prime Minister Taro Aso and South Korean President Lee Myung-bak agreed June 28 to intensify joint efforts to stop Pyongyang's nuclear programs and urged North Korea to abide by a U.N. Security Council resolution condemning its recent nuclear test.

Lee arrived in Tokyo on June 28 for a day of talks as part of the shuttle diplomacy designed to build closer relations between the two nations, after bilateral ties soured during the tenure of Lee's predecessor, Roh Moo-hyun.

"Japan, South Korea and the United States must work in coordination," Aso said.

"We must unite and properly handle the matter" to get Pyongyang to drop its nuclear programs and become part of the international community, Lee replied at the outset of the meeting as reporters watched.

North Korea has remained confrontational, announcing it will proceed with its uranium-enrichment program for military use, even though the U.N. has condemned the hermit state's May 25 nuclear test.

The June 28 meeting was the eighth the two leaders have had since Aso took office last September, with a Foreign Ministry official describing the frequent shuttle diplomacy as a sign of a "mature partnership."

"This was not a visit to resolve a pending matter, but an occasion for the two heads of state to speak frankly," the official said.

Even so, responding to North Korea's belligerence topped the agenda.

The two sides agreed that implementing the U.N. resolution is a vital step in facing the threat.