North Korea opened the first congress of its ruling Workers' Party in 36 years on Friday, with Kim Jong Un expected to further consolidate his control over a country that has grown increasingly isolated over its pursuit of nuclear weapons.

Secretive North Korea trumpeted "miraculous results" ahead of the event and said advances in nuclear and ballistic missile developments, made in defiance of U.N. sanctions, were "the greatest gifts" for the rare party congress, but little of substance was revealed.

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There was no word in Pyongyang from official sources about the proceedings other than that the meeting was under way. North Korean state media mentioned that congress would open on Friday but did not carry details of proceedings as of early evening.

The congress opened on a rainy morning. Covers were hung over the giant portraits of Kim's grandfather, Kim Il Sung, and father, Kim Jong Il, that adorn Kim Il Sung square in the capital.

Foreign journalists invited to cover the event were not permitted inside the April 25 House of Culture, the stone structure draped in red party flags where the congress is expected to run for several days.

Foreign analysts expect the third-generation leader of the Kim dynasty to formally adopt his "Byongjin" policy of simultaneously pursuing nuclear weapons and economic development, and to further consolidate his power.

"Kim is after catching two rabbits, a nuclear arsenal and economic development, and he's likely going to declare the country is a nuclear weapons state, so that's one rabbit," said Yang Moo-jin of the University of North Korean Studies in Seoul.

"He might also lay out a five-year or seven-year blueprint for the development of the people's economy," Yang said.

Kim has aggressively pursued nuclear weapons and ballistic missile technology. In March, the U.N. Security Council adopted the latest in a series of resolutions toughening sanctions against North Korea, which conducted its fourth nuclear weapons test in January.

Giant neighbor China, the North's lone major ally, backed the resolutions, growing frustrated over its nuclear tests.

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Chinese Foreign Ministry spokesman Hong Lei, asked about the congress at a daily briefing in Beijing, said North Korea was at an important stage in its national development.

"We also hope North Korea can listen to the voice of the international community, and jointly maintain northeast Asia's lasting peace and stability," Hong said.

Thousands of delegates from around North Korea had been expected to attend the first congress to be held since 1980, before the 33-year-old Kim was born. Security guards in suits and ties surrounded the venue.

The Byongjin policy follows Kim's father's Songun, or "military first" policy, and his grandfather's Juche, the North's home-grown founding ideology that combines Marxism and extreme nationalism.

State radio said the 7th Workers' Party congress would "unveil the brilliant blueprint to bring forward the final victory of our revolution," according to South Korea's Yonhap news agency.

North Korean state media has trumpeted a 70-day campaign of intensified productivity in the run-up to the congress, and Pyongyang has been spruced up for the event.

The state-run KCNA news agency cited advances in nuclear and ballistic missile development, crediting military scientists and engineers for accomplishments that are "the greatest gifts" for the party congress.

"Miraculous results were produced," KCNA said, touting production in the industrial sector that achieved 144 percent of target and electricity generation at 110 percent, although the actual targets were not given.

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Under Kim Jong Un, an informal market economy has been allowed to grow, although it has not been officially adopted as government policy.

However, more taxis and private cars on the streets, more goods in shops, and more buildings under construction attest to growing prosperity and consumption among Pyongyang residents.

South Korea has been on alert in anticipation that the North could conduct a fifth nuclear test to coincide with the congress. North and South Korea are still technically at war after their 1950-53 conflict ended in a truce, not a treaty.

North Korea's founding leader, Kim Il Sung, spoke for more than five hours at the last party congress. Kim Jong Il, who almost never spoke in public, did not hold a party congress.