Flights to New Zealand set to become even cheaper

The cost of flying between New Zealand and Australia looks set to drop as trans-Tasman red tape could be cut.

Australian and New Zealand customs last year reached an initial agreement to streamline travel between the two nations while boosting border security.

The plan to create a common border will allow trans-Tasman travellers to avoid customs and immigration, dropping flight prices by up to 30 per cent and allowing an explosion in potential new flight routes.

New Zealand Prime Minister John Key, who spoke to AAP before addressing a business forum in Brisbane on Tuesday, said he, together with Prime Minister Kevin Rudd, would formally announce the changes when they meet in a few weeks to discuss the bilateral Closer Economic Relations (CER) agreement.

"It is a positive announcement which will allow New Zealanders and Australians to cross each others' borders more easily," Mr Key said.

"It's an attempt to streamline the process and to ensure that it's a more seamless and painless process for Australians and New Zealanders as they travel across the border."

Any new rules would not affect quarantine or biosecurity "level of exposure" between the two countries, he said.

About one million Australians visit New Zealand each year.