Police have issued environmental protesters notices to ensure their boats do not get too close to an oil and gas survey ship or its support vessel off East Cape.
Brazilian company Petrobras is conducting a survey of 12,000 square kilometres of seabed determine if oil or gas are likely to be under the ocean floor in commercial quantities.
The company has a permit to search for oil and gas and a legal obligation to continue under the terms of an agreement with the New Zealand Government.
Since Sunday, a flotilla of boats protesting against deep sea drilling has prevented Petrobras from carrying out the exploration work, with protesters swimming in front of survey vessel the Orient Explorer in waters off the Raukumara Basin.
Superintendent Barry Taylor says police on Navy inflatable boats issued the notices to the protest flotilla's four skippers under the Maritime Safety Act on Tuesday.
The notices state the boats must stay 250 metres off the bow and stern of the survey ship, and 200 metres off its port and starboard sides.
Failure to comply could incur a fine of no more than $10,000 and up to 12 months in jail.
The protest coalition, which includes Greenpeace and members of a Maori iwi, is taking legal advice and discussing how to respond to the notices.
Company 'happy to wait'
Petrobras says it will continue the exploration when it believes it is safe to do so.
The company's asset manager for New Zealand, Marco Toledo, says Petrobras does not want the Government to do more to stop the protesters and is happy to wait.
Mr Toledo told a news conference on Tuesday that safety is the key priority in any of the company's projects and when it has those conditions again at East Cape the operation can proceed.
Petrobras says it respects the right to protest, but can not guarantee there are no environmental effects during drilling.
Mr Toledo says he does not think the protest action will have an impact on other oil companies doing business with New Zealand in the future.
Government sought legal advice
The Government asked Crown Law what powers police might have in this situation.
Acting Energy and Resources Minister Hekia Parata says police have jurisdiction over protesters and can take action when they think a law is being broken.
Ms Parata says Petrobras has a permit to operate and protesters can not infringe on the lawful activity of others. She has reassured the company it will be able to carry out its survey work.
Prime Minister John Key says some of the protest vessels have foreign flags, but that does not make a difference and action can still be taken against them.
But Maori Party MP Te Ururoa Flavell says the Navy should not have got involved in the protest, nor should military equipment be used during non-violent activities.
Mr Flavell says iwi Te Whanau A Apanui and Ngati Porou should have been consulted properly before the permit was given to Petrobras.