MGL chapter 41, Section 58. Whenever any appropriation shall have been expended or whenever, in the judgment of the town accountant, it appears that the liabilities incurred against any appropriation may be in excess of the unexpended balance thereof, he shall immediately notify the selectmen and the board, committee, head of department or officer authorized to make expenditures therefrom, and no claim against such appropriation shall be allowed nor any further liability incurred until the town makes provision for its payment. The town accountant shall, at regular intervals and as often at least as once each month, send to the selectmen and to each board, committee, head of department or officer having the disbursement of an appropriation a statement of the amount of orders approved and warrants drawn on behalf of said board, department or officer during the preceding month, and a statement of the balance of such appropriation remaining subject to draft. Each head of a department, board or committee authorized to expend money shall furnish the town accountant, at the close of the financial year, a list of bills remaining unpaid, showing to whom and for what due, and their amounts; and the town accountant shall incorporate the same in his annual report covering the financial transactions of the town, as provided by section sixty-one.