Prime Minister John Key appears to have subtly changed the criteria which the Prime Ministers must use before they admit potentially nuclear armed naval vessels.

Mr Key at his weekly post Cabinet press conference yesterday set out the criteria he will use to decide whether to admit a US naval vessel if the Americans accept an invitation to attend the Royal New Zealand Navy’s 75th anniversary next year.

Mr key believes that the question over whether American ships should visit New Zealand is not the same as it was in 1985.

“To me this sort of debate has been and gone,” he said.

“The Americans have got their own position.

“They had their own concerns at the time. I appreciate all those but New Zealand has changed its law and it’s not going to alter that law.

And successive governments – including mine – have confirmed that legislation was staying in place.”

The law Mr Key was talking about, the 1987 New Zealand Nuclear Free Act requires that the Prime Minister “may only grant approval for the entry into the internal waters of New Zealand by foreign warships if the Prime Minister is satisfied that the warships will not be carrying any nuclear explosive device upon their entry into the internal waters of New Zealand.”

The question that bedevilled the Lange Government when it turned the Buchanan down in 1985 was how it could be “satisfied.”

And what complicated that was that the United States Government refuses to confirm or deny whether a naval vessel is carrying nuclear weapons.

In 1985 that left Prime Minister David Lange and his deputy, Sir Geoffrey Palmer, having to rely on an intelligence analysis of whether the ship that was the potential visitor, the Buchanan, was carrying weapons.

This was famously summarised by the-then Defence Force Chief, Air Marshall Ewan Jamieson, who said: “I can give no absolute guarantee that the ship does not carry nuclear warheads … but after careful consideration I consider it most unlikely.”

It was that ambiguity which forced the Cabinet’s hand and they turned down the ship.

Mr Key said yesterday that the law was that the Prime Minister had to be able to believe that New Zealand was complying with its own legislation.

He said it was already in practice with requests from foreign air forces and navies to come to New Zealand and when they did he received a recommendation from the Ministry of Foreign Affairs that the visit complied with the nuclear free law.

“The only wat Foreign Affairs would provide that advice to me is when they are absolutely confident that that’s the case.

“How they achieve that level of confidence is a matter for Foreign Affairs but it isn’t a matter of us asking the Americans.”

So the difference between now and 1985 is that officials – presumably with input from Defence and intelligence agencies – will make a judgement about whether a ship is carrying the weapons and the prime Minister will accept their word.

But without a formal statement from the Americans it is hard to see how the Ministry could not append Air Marshall Jamieson’s qualification of being able to give no absolute guarantee to its advice to the Prime Minister.

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