The commissioner, upon request of the Federal Highway Administrator, Federal Highway Administration, Department of Transportation of the United States, may enter into agreements, subject to the limitations of § 13a-6, with the Federal Highway Administration for the making of surveys, plans, specifications and estimates for, and for the construction and maintenance of, roads and bridges necessary to provide access to military and naval reservations, to defense industries and defense industry sites and to sources of raw materials, and for replacing existing highways and highway connections shut off from public use at military and naval reservations and defense industry sites. Notwithstanding any other provisions of law, he may enter into contracts in any manner approved by said Federal Highway Administrator for the construction of any such roads or bridges, or may cause such construction and maintenance work to be performed by employees of the Department of Transportation of this state.