The Northern Territory Government says it did not have the power to stop a port development on Melville Island from going ahead on environmental grounds.

It also said it does not have a minister responsible for signing off on port developments.

The statements came as two NT ministers fronted the media on Wednesday for the first time since the ABC reported that a deep sea port was being built in an area listed as significant to wildlife, without environmental approval at the Territory or Federal level.

NT Environment Minister Gary Higgins said a loophole in planning laws allowed the port to be constructed without an environmental impact statement (EIS) and despite no minister signing off on the project.

Mr Higgins said developers were supposed to submit to him environmental impact statements if required by the NT Environmental Protection Agency (NTEPA), and Mr Higgins would then pass on those statements to the responsible minister.

"The responsible minister for port development is a loophole in the legislation," Mr Higgins told reporters.

"There is no responsible minister for signing off on a port development."

Port Melville on the Tiwi Islands, 80 kilometres north of Darwin, was not referred to the Federal Environment Department for environmental assessment either, despite the Tiwi Islands being a habitat to threatened and migratory wildlife species.

Mr Higgins said that in relation to Port Melville there was no EIS completed, and a Notice of Intent was not done to the satisfaction of the EPA.

"The legislation is there, it's simply when people don't abide by the legislation that we lack a bit of teeth in that area," Mr Higgins said.

He baulked at a suggestion the situation was a "fiasco".

"If there had been a major environmental disaster come out of this, well then possibly you could describe it as that [a fiasco] but at this point there hasn't been any environmental disaster as far as I am aware," Mr Higgins said.

Mr Higgins said there was a review of the relevant legislation that had been underway for the past six months but added that he did not know when it would be completed.

'Proper processes were followed' says Chandler

Earlier the NT's former planning minister Peter Chandler, who now holds a range of other ministerial responsibilities, said "proper processes were followed" in the construction of Port Melville, despite the head of the NTEPA saying the information received from the company was "deficient".

The statement from Mr Chandler, who was lands and planning minister during the time the construction commenced, comes a day after Federal Environment Minister Greg Hunt ordered an investigation "as a matter of priority" into the construction of a port on the Tiwi Islands.

His statement comes after the ABC revealed the deep sea port 80 kilometres north of Darwin, was not referred to the Federal Environment Department for environmental assessment despite the Tiwi Islands being a habitat to threatened and migratory wildlife species.

"I know there was EIS (Environmental Impact Statements) involved in this process," Mr Chandler said.

NTEPA chairman Dr Bill Freeland told ABC radio yesterday they had requested environmental information from Singaporean-based Ausgroup more than 12 months ago but the response they received "was so deficient in information we had to request additional information ... we are still waiting for it".

However, Mr Chandler told reporters on the Tiwi Islands today he was given a very detailed briefing "on all the environmental approvals that [the company] had to go through".

When asked where EIS documents for the project could be publicly viewed, Mr Chandler referred reporters to the NTEPA.

"They are the people that are responsible to ensure that our environment is protected. They are the people that are responsible to keep an eye on and ensure that project managers out there are doing the right thing.

"But I am very confident that the right thing is being done here and that the project manager is doing all they can to ensure that the environment is being protected."

'They can actually ignore it'

Dr Freeland said the company had not abided by the spirit of the Northern Territory Environmental Approval Act.

"They can actually ignore it ...and that is just the way it is," he said.

Pressed on the process for approving Port Melville's development, Mr Chandler said it was the responsibility of the EPA and the Federal Government to step in if they believed a development was not fit for approval.

Storage tanks on Port Melville, on the Tiwi Islands which can store up to 30 million litres of diesel. ( Supplied )

"People can be absolutely assured today that when any development is occurring that not only do you have the NT Government and the EPA ensuring that the environmental credentials are there, you also have the Federal Government that has the right at any time, to make sure the right thing's being done," he said.

Dr Freeland said the EPA does not have the power to approve or deny approval for development.

"[There are] gross deficiencies in the act which make our job extremely difficult," Dr Freeland said.

"I have no powers to approve or not approve [projects]. We only provide recommendations [to government]."

Ausgroup executive director Larry Johnson told News Ltd the company had been dealing with environmental assessment agencies "for about two years, both federally and in the Northern Territory".

Mr Johnson said Port Melville is operating on a site that already has approvals.

"We are working within the same footprint as the previous operations," Mr Johnson is reported as saying.