N.H. Rev. Stat. Ann. § 33:9

The issue of bonds or tax anticipation notes by a city shall be authorized by a resolution of the city councils, passed by at least 2/3 of all the members of each branch thereof. All such bonds and notes shall be signed by a mayor and countersigned by the city treasurer, and shall have the city seal affixed thereto. The discretion of fixing the date, maturities, denominations, place of payment, interest rate, or discount rate in the case of notes, the form and other details of said bonds or notes, and of providing for the sale thereof, may be delegated to the city treasurer and shall, to the extent provision therefor shall not have been made in the vote authorizing the same, be deemed to have been delegated to the treasurer with approval of the mayor.