a. In the case of any contract which is let by other than competitive sealed bidding, the mayor shall certify, prior to the filing of the contract with the comptroller for registration in accordance with section three hundred twenty-eight of this chapter, that the procedural requisites for the solicitation and award of the contract have been met. The mayor may delegate such function to the agency proposing to award a contract only upon adequate assurance of an agency's capacity to comply with procedural requirements.
b. The corporation counsel shall certify prior to the filing of a contract with the comptroller for registration in accordance with section three hundred twenty-eight of this chapter, that each agency proposing to award a contract has legal authority to award each such contract.