South Korean President Lee Myung- bak on Tuesday called on member states of the six-party talks to take united actions to deal with the Democratic People's Republic of Korea (DPRK)'s unclear ambitions, according to a Yonhap report.

Lee made the call during a joint interview with South Korea's Yonhap News Agency and Japan's Kyodo News Agency at the presidential office Cheong Wa Dae.

Although Pyongyang offered a series of conciliatory gestures recently, it still failed to show its willingness to completely abandon its nuclear program, Lee said.

The president said he believe that Pyongyang's recent conciliatory moves only resulted from the impact of tighter U.N. Security Council sanctions.

"I believe North Korea was thrown off because these measures ( sanctions) are having a stronger impact than earlier anticipated," he said.

"As a result of North Korea facing such a crisis, it is taking somewhat reconciliatory gestures toward the United States and South Korea to avoid the situation. But it is still not showing any sincerity or signs that it will give up its nuclear ambitions, " Lee said.

The DPRK recently made a series of reconciliatory gestures toward Washington and Seoul, such as freeing two detained American journalists during former U.S. President Bill Clinton's trip on Aug. 4, and then releasing some South Korean detainees, agreeing on holding talks for separated families' reunion, lifting restrictions on inter-Korean border traffic, and restoring a military hotline with South Korea.

But on the other hand, it claimed that the reprocessing of spent fuel rods "is at its final phase and extracted plutonium is being weaponized," and the "experimental uranium enrichment has successfully been conducted to enter into the completion phase," which was described by Seoul as "two-track strategy."

The two-track strategy can be seen as Pyongyang's attempt to receive economic cooperation while "buying time" through the conciliatory gestures to make the possession of nuclear arms an accomplished fact, Lee said.

"That is why member countries of the six-party talks must double their efforts to persuade North Korea to give up its nuclear ambitions through a unified strategy," Lee said.

The six-party denuclearization talks involve the South Korea, the DPRK, the United States, China, Japan and Russia.

(Xinhua News Agency September 15, 2009)