Official papers reveal the Treasury and the State Services Commission opposed plans to set up an independent workplace health and safety regulator.
The Government announced in February it expected to have the new agency operational by December.
The Treasury and the State Services Commission worried that ministers would have less influence over the proposed agency and that it would lead to duplication and more bureaucracy.
The Ministry of Business, Innovation and Employment has responsibility for workplace health and safety at the moment.
The ministry said setting up an independent agency would help give public confidence in the workplace health and safety regime a short-term boost.
Setting up the agency was also the first recommendation made by the Royal Commission on the Pike River Mine tragedy.