Charles Robert Jenkins, a US soldier imprisoned for deserting to North Korea, may be released early, reports quoting Japanese media say.
Jenkins' case has been closely followed in Japan
Japan's Kyodo news reportedly said Jenkins, 64, would be released from a US naval base in Yakosuka on Saturday.
Jenkins, who ended up living in the North for 39 years, was found guilty of desertion earlier this month and sentenced to 30 days in jail.
Kyodo said Jenkins wants to live in his Japanese wife's hometown in Niigata.
He was originally due to be released on 3 December, but Japanese media said he had had his sentence reduced for good behaviour.
The early release date has not been confirmed by US or Japanese authorities.
Kyodo said Jenkins wanted to use his freedom to find a job on Sado island, where he plans to live with his wife and their two North Korea-born children, Mika, 21, and Brinda, 19.
The agency quoted the mayor of Sado, Koichiro Takano, as saying he would discuss with Jenkins what kind of job would be appropriate.
Jenkins has pleaded guilty to desertion to North Korea in 1965, when he was on patrol in South Korea for the US military.
He told the court that he wanted to avoid "hazardous" duty on the Korean peninsula and in Vietnam.
Jenkins gave himself up to the US in September, while in Japan for medical treatment.
He left North Korea in July, when the authorities there allowed him to visit Indonesia for a supposedly brief reunion with his family, but he went on to his wife's home country.
His case has been closely watched in Japan, especially because his wife, Hitomi Soga, was one of five Japanese abducted by North Korea and freed in 2002.
The couple met and married in North Korea.