Antonyms for "giving the go-ahead" include "putting a stop to," "blocking," "prohibiting," "refusing," and "withholding approval." Contrasted with "giving the go-ahead," these terms suggest an atmosphere of restriction, inhibition, or denial. For instance, blocking a proposal may imply a lack of trust, confidence, or support towards those making the proposal. Prohibiting a project may indicate a conflict of interest or values, as well as a fear of negative consequences. Refusing or withholding approval may reflect a dissenting voice, a prior commitment, or a belief that alternative options are more suitable. In short, antonyms for "giving the go-ahead" underscore the importance of communication, negotiation, and compromise in decision-making processes.