The Adjutant General of Mississippi, in his discretion, subject to the approval of the Governor and the Attorney General, is hereby authorized and empowered to execute leases to the United States of America on lands held through deed or lease by the State of Mississippi for National Guard purposes, for the purpose of securing construction of Air National Guard armories thereon at the expense of the federal government. Likewise, the governing board of any county, municipality or school district is authorized to lease lands to the United States for such purpose, and the Adjutant General of Mississippi and said governing boards are authorized to execute such instruments as may be necessary to carry out the purposes of this section.