Section 5
SEC. 5. The authority herein granted to the agency head concerned shall be subject to the provisions and requirements of existing laws and regulations on the awarding and execution of contracts for public works and the expenditure of public funds: Provided.That no contract for the construction of public works projects included in or covered by the Public Works Act shall be entered into and executed under this Act unless the Commissioner of Budget shall have certified that funds equivalent to the contract price have been duly appropriated and allotted from funds certified as available for the purpose.