Answer: I would reject his demand for bribe straight away and i will recommend senior management to protect business ethics at all cost.
Explanation: first of all i would not accept the demand of bribe from the official and would try to report this corruption to the concerned authorities.I would try to pressure the authorities to take strict actions against the official and to make the process to be fair and honest in every way.
I as a representative of my company would recommend senior management to take hands off from the project until appropriate actions are taken by the authority as getting into unethical actions might result in problems in future .