Japan and China are ready to start full negotiations this year on two possible treaties for prisoner transfers and extradition of criminals, following another being discussed to boost cooperation in criminal investigations, according to Japanese sources.

Both countries see a clear path to a substantive agreement on a treaty for cooperating in criminal investigations by the end this year, a goal confirmed by Prime Minister Shinzo Abe and Premier Wen Jiabao during their talks in Tokyo last month, the sources said.

The envisaged treaty on prisoner transfers is aimed at enabling people to do time in their home country for crimes committed in the other country, while the extradition treaty would set conditions and rules for handing over suspects.