Kim Dong Chul, who previously said he was a naturalised American citizen and was arrested in North Korea in October, asked for mercy during a meeting with media organisations in Pyongyang, Kyodo said.
Kim apologised for trying to steal military secrets in collusion with South Koreans and described the acts as aimed at overthrowing the North Korean regime, Kyodo said.
A source in Pyongyang told Reuters on Friday that diplomats in the North Korean capital were notified in the morning of Kims confession and his comments were similar to the confession made by another American, Otto Warmbier, being held in the North.
Warmbier was sentenced to 15 years of hard labour earlier this month for trying to steal a propaganda banner, and the North is also holding a Korean-Canadian Christian pastor, who is serving a life sentence for subversion.
An official introducing Kim to the media began the meeting by praising North Koreas nuclear achievements and its leader Kim Jong Un, said the source, who had direct knowledge of the meeting.
A defector from the North previously told Reuters that Kim, who is one of three known Western citizens held in the North, was a Christian pastor who had worked in China and the United States and sent medical aid into the North.
CNN reported in January that Kim was 60 and from Fairfax, Virginia, and that he said he had spied on behalf of South Korea.
North Korea, which has been criticised for its human rights record, has in the past used detained American citizens to extract high-profile visits from the United States, with which it has no formal diplomatic relations.
It faces the prospect of further international isolation after the U.N. Security Council imposed new sanctions after its fourth nuclear test in January.
Editor: Priyambodo RH
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