SINGAPORE - The chief nuclear negotiator of the Democratic People's Republic of Korea (DPRK) and former senior officials and scholars from the United States were in Singapore on Sunday for a unofficial meeting over topics including the DPRK nulcear issue.

Leon Sigal, director of the Northeast Asia Cooperative Security Project at the US-based non-profit organization Social Science Research Council, told reporters that the meeting will cover the DPRK's nuclear missile programs.

"It's two ways of taking each other's temperature," he said.

The DPRK side is led by Ri Yong Ho, the DPRK's Six-Party Talks representative, while the US team includes former US special representative for DPRK policy Stephen Bosworth, former deputy nuclear negotiator Joseph DeTrani, and Tony Namkung, former deputy director at Berkeley's Institute for East Asian Studies.

The two-day meeting, which is unofficial, is taking place at a local hotel behind closed doors. Police were seen handling secuirty matters, and the participants were seen stepping out for breakfast and lunch on Sunday.

The US Embassy in Singapore, which had been tight-lipped on details of the meeting, said in a statement that "this would be one of many Track 2 meetings held to discuss East Asia political and security issues."

"The US government is not involved in the proposed event," the embassy added.

Track 2 diplomacy often refers to non-governmental, informal and unofficial contacts and activities between private citizens or groups of individuals.

The Democratic People's Republic of Korea (DPRK) has recently conveyed its willingness to resume DPRK-South Korea summits and hold direct dialogue with the United States. It also said that the DPRK side is willing to temporarily suspend its nuclear tests if the United States, in exchange, suspends joint military drills with South Korea. The proposal was rejected by the United States.