Once the Trans Pacific Partnership talks conclude, New Zealand and the 11 other countries must tick several boxes before the agreement can be brought into force.
Under a rule set by the United States, any agreement cannot be signed until 90 days after negotiations end, to allow time for full consideration of its pros and cons.
The same rule also says the agreement's full text must be made available to the public after 30 days.
In New Zealand, the Ministry of Foreign Affairs will provide a report to the Cabinet on the costs and benefits.
The Cabinet will then decide whether to approve the agreement.