N.H. Rev. Stat. § 236:83
The commissioner of transportation may enter into agreements with the Secretary of Transportation or appropriate federal official of the United States as provided by section 131 of Title 23, United States Code, provided that any such agreement shall be consistent with, and not more restrictive than, the provisions of this subdivision, except that the reclassification of the federal aid systems from time to time shall not be considered more restrictive than the provisions of this subdivision, and except that the agreement executed by the former commissioner of public works and highways and the federal highway administrator on June 14, 1963, under the provisions of this subdivision is hereby reaffirmed so that the commissioner of transportation may maintain the control required to receive and to continue to receive bonus payments from the federal government with respect to the control of outdoor advertising on the interstate system. Any expenditures of money by the commissioner in connection with agreements authorized by the section shall be payable from any funds available to the commissioner.
RSA 236:83
RSA 249-A:14. 1969, 429:1. 1971, 245:1. 1981, 87:1. 1985, 402:6, I(b)(7). 1987, 209:6, eff. July 14, 1987.