DALIAN, China (Yonhap News) ― Senior officials from the six nations involving in stalled talks on North Korea’s nuclear program gathered Thursday at an annual security conference here, where long-standing tensions over the North’s nuclear ambition are likely to top the agenda, a diplomatic source said.

The Northeast Asia Cooperation Dialogue drew government officials and civilian experts from South Korea, North Korea, the United States, China, Japan and Russia to this eastern Chinese port city of Dalian for the two-day, closed-door forum.

Organized by the University of California Institute on Global Conflict and Cooperation, the NEACD has served as an opportunity for informal dialogue between North Korea and its nuclear negotiation partners. Last year’s meeting was held in Hawaii, but North Korean officials did not attend.

North Korea sent its deputy chief envoy to the six-party talks, Choe Son-hui, to the conference and other nations also dispatched their deputy chief nuclear envoys to the Dalian forum.

It is the first time since 2009 that representatives from all nations participating in the six-party talks joined the NEACD conference.

The U.S. State Department has ruled out the possibility of a bilateral meeting with the North Korean representative during the forum.

The six-party talks were last held in late 2008 and diplomatic efforts to resume negotiations have been frozen since April, when North Korea defiantly launched a long-range rocket that failed moments after lift-off.