Where a bridge, other than a toll bridge, forming part of a State highway or a continuation thereof, or connecting two State highways, hall be owned or controlled in whole or in part, by any person, partnership, association or corporation, it shall be lawful for the secretary with the approval of the Governor, to enter into agreements with such owner for the acquisition of such bridge or bridges, or for the division of responsibility for maintenance thereof, under such fair and reasonable terms of payment as may be agreed upon: Provided, however, That this section shall not apply to relieve any person, partnership, association or corporation from any obligation for the construction or maintenance of any such bridge under any agreement or order of court, or any order of the Public Utility Commission, heretofore or hereafter made.