(Steps taken by the Minister of Foreign Affairs upon receipt of a request for surrender)
Article 3.
(1) When, in the case of a request which has been made pursuant to a treaty of extradition, it is deemed that the form of the request is not consistent with the requirements of the treaty of extradition;
(2) When, in the case of a request which has not been made pursuant to a treaty of extradition, the requesting country has not assured that it would honor a request of the same kind made by Japan.
Contents of request for arrest and surrender
Contents of request for arrest and surrender - national law requirements
EDIT.