The Justice Ministry will seek Diet approval for the ratification of an international convention on prisoner transfers during an ordinary session to open early next year, it was learned Wednesday.

The move is designed to enable non-Japanese who have been convicted of a crime to serve their sentence in their home country, thus facilitating their return to society, ministry officials said.

According to government statistics, the number of non-Japanese convicted of crimes here has more than doubled in the past 10 years. The rationale behind the convention is the difficulty in creating an environment for foreigners to be rehabilitated due to differences in areas such as language and customs.

If Japan ratifies the convention, it would also pave the way for Japanese convicted overseas to return to serve their time in Japan.

According to Justice Ministry officials, the convention was drawn up in 1983 and took effect in 1985. At present, 44 nations are signatories to to the agreement and signatories can transfer convicts between each other.

The conditions stipulated under the convention for such transfers include:

* The crime for which the criminal has been convicted is also a legal offense in his or her home country;

* Both countries agree to move the convict;

* The convict requests or agrees to the transfer;

* At least six months of the sentence remain.

While those serving sentences with no set term will be covered by the convention, those on death row will not.

Probation and correctional matters after the convict has been returned to his or her country will be left in the hands of that nation. Reduction of terms and amnesty would also be possible.

The moving of convicted criminals was first debated about two years ago, at the request of the United States.

Although the Justice Ministry initially planned to draw up a bilateral agreement between Japan and the U.S., it decided to ratify the convention as this would achieve the goal sooner, according to ministry officials.

As of the end of 1999, 2,838 non-Japanese were serving prison terms in Japan, up from 1,380 in 1990. The figure has been increasing steadily since the 2,000 mark was breached in 1996, government statistics show.

Government officials said that as of January 1999, 140 Japanese were serving time in prisons overseas, more than 100 of those in Asia and North America.