11. If, upon receipt of the report and statement under clause (b) of section 10, the Government is of opinion that the fugitive offender ought to be surrendered, it may issue a warrant for the custody and removal of the fugitive offender and for his delivery at a place and to a person to be named in the warrant: Provided that the fugitive offender shall not be so delivered until after the expiration of fifteen days from the date he has been taken in custody under such warrant.