(a) The FHWA Administrator shall review the State request, determine whether sufficient Federal-aid urban system funds are available, and notify the State highway agency and the UMTA Administrator of the reservation of funds.

(b) The apportioned funds reserved for the proposed project under paragraph (a) of this section shall remain available for obligation unless the FHWA Administrator is notified that the application has been disapproved by the UMTA Administrator, or unless the responsible local officials in whose jurisdiction the project is to be located and the State highway agency jointly request the withdrawal of the project application.