SINGAPORE - The chief nuclear negotiator of the Democratic People's Republic of Korea (DPRK) said on Monday that he has explained the intentions and purpose of the recent proposal put forward by the DPRK at an unofficial meeting here with former senior officials and experts from the United States.

"We provided detailed information of the intentions and purpose of this proposal," Ri Yong Ho, the DPRK's Six Party Talks representative, told reporters after the two-day meeting in Singapore.

Ri said that the root cause aggravating the tension on the Korean Peninsula is "none other than" the large-scale joint military exercises between the United States and South Korea which has been held annually.

"To put an end to this large-scale joint military exercise...is the first step towards easing the tension on the Korean Peninsula," he said.

Asked what pre-conditions the DPRK is setting for it to return to the six-party talks, Ri said "For the first time, we had proposed the meeting without any preconditions."

The closed-door meeting in Singapore concluded on Monday. Former U.S. special representative for DPRK policy Stephen Bosworth, one of the U.S. participants in the meeting, said that the two sides also had extensive exchanges of views as to the atmosphere in the United States.

"We had very useful discussions of not so much what's happened but what could happen in the future," he said, reading a prepared statement.

Bosworth, who emphasized that he and his colleagues from the United States were participating in the meeting as private citizens, said that the priority for the U.S. side is the need to get official discussions underway, resume the multilateral talks and deal with the issues of denuclearization and other elements of the joint statement from the Six-Party talks of September 2005.

He said that there is no plan for a next meeting at present.

The meeting in Singapore came after the United States rejected the proposal by the DPRK that it stands ready to suspend its nuclear tests if the United States suspends its annual joint military exercises with South Korea.

The United States has obviously downplayed the importance of the meeting, with its embassy in Singapore saying that the U.S. government is not involved.

Leon Sigal, director of the Northeast Asia Cooperative Security Project at the U.S.-based non-profit organization Social Science Research Council, told reporters that the meeting would cover the DPRK's nuclear missile programs. "It's two ways of taking each other's temperature," he said on Sunday.

The six-party talks had been bogged down since Pyongyang pulled out in April 2009 in response to a UN Security Council presidential statement condemning its rocket launch. Amid rounds of crippling sanctions and repeated U.S.-South Korea joint military drills, the DPRK has so far conducted three nuclear tests.

Despite the precarious character of the sexpartite framework, the six-party talks remain the most viable platform to achieve peaceful denuclearization of the Korean Peninsula and realize lasting stability in Northeast Asia.

Launched in 2003, the six-party talks involves China, Japan, Russia, South Korea, the United States and the Democratic People's Republic of Korea (DPRK) to negotiate a solution to the Korean Peninsula nuclear issue.

On Sept. 19, 2005, the six parties wrapped up their fourth round of talks with a joint statement that is widely considered as the most important agreement ever achieved so far in the stop-and- go undertaking.

The document affirmed the goal of verifiable denuclearization of the Korean Peninsula in a peaceful manner. The DPRK committed itself to abandoning all nuclear weapons and existing nuclear programs but insisted on its right to peaceful uses of nuclear energy.

The United States affirmed that it has no nuclear weapons on the Korean Peninsula and has no intention to attack or invade the DPRK with nuclear or conventional weapons. South Korea reaffirmed its commitment not to receive or deploy nuclear weapons on the Korean Peninsula and affirmed that there existed no nuclear weapons within its territory.

The six parties also agreed to take coordinated steps to implement the consensus in a phased manner in line with the principle of "commitment for commitment, action for action."