The Workers' Party of Korea, the ruling party of the Democratic People's Republic of Korea, opened its 7th Congress on Friday.
It is the first WPK congress in 36 years and the first under the leadership of Kim Jong-un.
Analysts say the congress may focus on further consolidating the policy of simultaneously developing nuclear weapons and the national economy, and might emphasize the DPRK's status as a nuclear state.
An estimated 3,000 party representatives will attend the meeting, which presumably will last three days.
More than 100 foreign journalists were denied access to the assembly hall. They were asked instead to stay outside the meeting venue and interview Pyongyang residents.
Yoon Hae-ryoong, a senior majoring in mechanics at Kim Il Sung University, told Xinhua that he sees the congress as a historical watershed in the revolutionary cause of the DPRK. He said that as a young college student, he was lucky to take part in the parade and torch march before the meeting.
He said the concurrent development of nuclear weapons and the national economy is a long-term strategic approach to dealing with "US imperialists".
The DPRK official media has not reported on the congress.
In Beijing, Foreign Ministry spokesman Hong Lei said that China hopes the DPRK can "achieve national development" and "heed the calls of the international community and work with us to maintain peace and stability in Northeast Asia".
Pyongyang had announced in late October that the 7th WPK congress would be convened in early May. The 6th Congress was held in 1980.