The modernization and the construction of arterial highways which are to pass through cities, will contribute greatly to post-war reemployment and to the stimulation of industrial recovery. The resources and the technical skills that are available to the state for these purposes, should be used for the benefit of the cities upon the principle that the construction of such arterial highways is a matter of state concern. However, it is the manifest intention of the state to recognize and to preserve the powers or rights heretofore conferred upon or delegated to any city to regulate the property, affairs or government thereof, in the modernization and the construction of such arterial highways. The integration of such arterial highways in the system of state highways throughout the state contemplates an expenditure of public funds to pay the costs that are attendant upon the fulfilment of a program of the work of modernization and construction as herein mentioned, as well as of the maintenance of such public ways. It is hereby declared to be the purpose of this act to initiate the procedure that is prerequisite to any project of the magnitude herein provided, to the end that orderly progress and equitable distribution of effort and moneys may be observed in the administration of this article, and, from time to time, when expressly authorized by the legislature, any section of such arterial highways may be constituted, constructed, reconstructed, improved and maintained as a part of the state highway system.