Palmerston North Mayor Jono Naylor has hit out at Hamilton Airport's bid for a government-funded runway extension as "ludicrous".

Hamilton Airport is lobbying to snatch the Ohakea Air Force Base's role as the North Island emergency-landing alternative to Auckland.

The airport company wants $25 million from the Government to extend its runway so it can land big jets if Auckland Airport is struck by a tsunami or any other calamity.

At the moment Ohakea is the default option for long-haul jets if both Auckland and Christchurch airports are closed.

But Mr Naylor said any taxpayer investment in Hamilton was "a waste of money" given Ohakea was already capable of stepping up in a civil defence emergency.

"But if the Government is of a mind to spend that much money on a regional airport we would like some too, please."Rangitikei MP Ian McKelvie said Ohakea could adequately carry out the emergency role without duplication in Hamilton.

It was improving its facilities to handle international passengers, he said. In the past, people on grounded international flights had been unable to disembark there.

Palmerston North Airport is able to accommodate smaller aircraft, including international flights, that are diverted from Wellington.

Hamilton Airport company chairman John Birch is promoting the proposed development at Waikato as providing a "national asset".

The other options were Ohakea, which was six or seven hours' drive south; Wellington, where the runway was about the same length as Hamilton's; Whenuapai, which could be affected by the same disaster as Auckland; and Christchurch.

None of them offered realistic propositions for "shuffling people north".

Palmerston North and Ohakea are already capable of providing the first civil defence response for Wellington if it suffers a catastrophe on the scale Mr Birch was anticipating for Auckland.

Palmerston North Airport chief executive Darin Cusack said they provided day-to-day back up for Wellington when flights were diverted. It hosted about 130 diversions a year. Even though it no longer had regular international flights, it was able to host international services on a "gas and go" basis which left passengers waiting on board until aircraft got clearance to continue to Wellington.

It would be able to step up to handle international passengers if the closure in Wellington was going to be extended.

Mr Davies said it would be harder to support Auckland from this distance, but it was possible.

"You would have to consider that if Auckland had a major issue, so too, might Hamilton."

Hamilton Airport has resource consent, subject to three appeals, to extend the runway to 2900 metres that would enable the new Boeing 777 and 788 to land.

- © Fairfax NZ News