40 U.S.C. § 601

In order to provide an economical and efficient system for transportation of Federal Government personnel and property consistent with section 101 of this title , the purposes of this subchapter are— (1) to establish procedures to ensure safe operation of motor vehicles on Government business; (2) to provide for proper identification of Government motor vehicles; (3) to establish an effective means to limit the use of Government motor vehicles to official purposes; (4) to reduce the number of Government-owned vehicles to the minimum necessary to transact public business; and (5) to provide wherever practicable for centrally operated interagency pools or systems for local transportation of Government personnel and property.