SEOUL - A senior Chinese Communist Party official will visit North Korea as early as Saturday, in what appears to be a move to press Pyongyang to return to nuclear disarmament talks, a South Korean news agency said on Friday.

The North said separately it was releasing a U.S. activist it had held since December, clearing an obstacle between North Korea and its most important dialogue partner, the United States, that could have harmed negotiations.

The moves comes as pressure is mounting on North Korea to end its year-long boycott of international nuclear talks and win rewards that can prop up its broken economy.

Communist Party international affairs chief Wang Jiarui is due to make the visit, Yonhap said citing diplomatic sources in Beijing and Seoul. The visit should take place on Saturday or next week, it said.

Wang met North Korean leader Kim Jong-il last year and received a denuclearization pledge.

China, the destitute North's biggest benefactor, is seen as having the most influence on the reclusive state. Kim Jong-il told the Chinese premier in October that he could return to the nuclear talks if conditions were right.

U.N. sanctions imposed after the North's nuclear test last year have dealt a blow to its wobbly economy, and a botched currency reform measure undertaken late last year deepened economic woes.

This will be a very difficult year, a year of crisis for North, said Cho Min, of the Korea Institute of National Unification. The visit may turn out to be the only way to get the urgent transfusion.

CHRISTIAN MISSION

North Korea said it was releasing U.S. activist Robert Park, 28, who walked over the frozen Tumen river from China and into North Korea on Christmas Day on a mission to raise awareness about Pyongyang's human rights abuses.

The North's official KCNA news agency said Park had confessed to illegally entering the state and that he had changed his mind about North Korea after receiving kind treatment.

North Korea said in late January that it was holding a second American for illegal entry. The man has not been identified.

(Additional reporting by Rhee So-eui; Editing by Nick Macfie)

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