酌定

make a decision as one sees fit;use one’s dicretion;be left to the discretion of;be at the discretion of…
对于办理有效期更长的签证，可根据派遣国政府的要求作为个案处理，由接受国政府～。Longer validity visas may be issued on a case--by-case basis upon request of the sending government and at the discretion of the receiving government.