(a) A contract between the municipality and an authority may be pledged by the authority to secure its bonds. A pledged contract may not be modified except as provided by the terms of the pledge. The governing body of the municipality may authorize the contract without further authorization.
(b) A payment required by the municipality under the contract may be made even if the payment is not provided for in the budget of the municipality, but the payment shall be included in subsequent budgets of the municipality.