The son of the pro-Pyongyang General Association of Korean Residents in Japan chief has been handed a suspended prison term for illegally importing mushrooms from North Korea.

Ho Jong Do, 50, was sentenced in the Kyoto District Court on Thursday to one year and eight months in prison, suspended for four years.

His father Ho Jong Man is the chairman of the association, called Chongryon.

Facing the same charges, Kim Yong Jok, 70, president of a Chongryon-affiliated trading firm, was sentenced to two years in prison, suspended for four years, with the court determining that Kim was the one who "planned and played a leading role" in the importation.

Presiding judge Makoto Wada said in the ruling that Ho "knew about the situation as an employee (of Kim's company) and was involved in the case as his job."

Wada also said that the two behaved in a "highly antisocial manner" by ignoring economic sanctions imposed by Japan against North Korea over Pyongyang's nuclear and missile development programs. The sanctions include banning imports from North Korea.

According to the ruling, the men allegedly imported about 3,000 kg of matsutake mushrooms produced in North Korea, worth around ¥7.6 million, via China in September 2010.

During the trial, Ho pleaded not guilty, saying that he had not known about the import. But Kim admitted to the charges and indicated the involvement of Ho. Prosecutors had sought a two-year prison term for each of the men.

Kim's company, based in Tokyo, was fined ¥2 million in line with prosecutors' requests.

Japanese investigators have alleged North Korea aimed to obtain foreign currency by exporting the highly sought-after mushrooms.

Chongryon has effectively functioned as North Korea's embassy for decades in the absence of diplomatic relations between Tokyo and Pyongyang.