The Secretary of State, the Secretary of Health and Human Services, and the Attorney General shall designate Federal employees and may, from time to time, designate private citizens to serve on an interagency coordinating group to monitor the operation of the Convention and to provide advice on its implementation to the United States Central Authority and other Federal agencies. This group shall meet from time to time at the request of the United States Central Authority. The agency in which the United States Central Authority is located is authorized to reimburse such private citizens for travel and other expenses incurred in participating at meetings of the interagency coordinating group at rates not to exceed those authorized under subchapter I of chapter 57 of title 5 for employees of agencies.