Mr Mark says it's particularly concerning considering the Government wants to add a further 620,000 square kilometres to the Navy's patrol zone with the creation of the Kermadec Ocean Sanctuary.

"How does the Government plan to protect, monitor and patrol the Kermadecs from here in New Zealand on the current figures? Nine days at sea this year so far on fisheries patrol?

"Did they know when they were standing up at the United Nations, telling people they were creating this massive marine reserve, that they actually had the ability to control and monitor it?" says Mr Mark.

Mr Mark claims the reason so many ships in the fleet aren't being used is because there aren't enough seamen to properly operate them. Mr Brownlee dismisses those claims, and says the Navy's quite capable of putting a full flotilla to sea.

Mr Brownlee blames the last Labour government for ordering too many in-shore patrol vessels and not enough off-shore vessels like the HMNZS Otago and Wellington.

"It's an extraordinary situation. I cannot believe the previous Government actually committed to that number without some idea if they'd use them. What we could do with more of is off-shore patrol boats.

"You'll have to go back to the Foreign Minister of the day and ask him why we were purchasing them at the time," he says.

"They've proved themselves to be completely inappropriate for the sort of seas that we have around New Zealand. They're only about 36 metres I think, so relatively short ships. Once they get out past the EEZ, they're pretty much a bit of a danger."

He defends the lack of sea days clocked up, and says they're busy with scheduled maintenance or other exercises.

"They're not going to sea for very good reasons. You have a number of days at sea, and then a number of days in port, probably a greater number of days, when maintenance is being done or crews are in some other form of training."

The ships need to stay maintained, says Mr Brownlee, because the Government wants to one day recoup its costs.

"The military disposal process is not as straightforward as just sticking them on Trade Me or some international magazine. You've got to go through a reasonably tight process because we are part of an international alliance. You don't want some of this equipment getting into the wrong hands."

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