Any judge or magistrate judge of the United States, when ordering a person released under chapter 207 on a condition of his subsequent appearance before that court, any division of that court, or any court of the United States in another judicial district in which criminal proceedings are pending, may, when the interests of justice would be served thereby and the United States judge or magistrate judge is satisfied, after appropriate inquiry, that the defendant is financially unable to provide the necessary transportation to appear before the required court on his own, direct the United States marshal to arrange for that person's means of noncustodial transportation or furnish the fare for such transportation to the place where his appearance is required, and in addition may direct the United States marshal to furnish that person with an amount of money for subsistence expenses to his destination, not to exceed the amount authorized as a per diem allowance for travel under section 5702(a) of title 5, United States Code. When so ordered, such expenses shall be paid by the marshal out of funds authorized by the Attorney General for such expenses.