Some companies are also offering packages that allow users to cap and control their data usage.
The final report and joint Government responses, to be released today, will say that without further action there is every indication the prices will stop falling and, in fact, may start rising again.
Ms Gillard and Mr Key are due to hold formal talks this morning. Last night, they had a private dinner with just them and their spouses, Bronagh Key and Tim Mathieson.
The NZ Commerce Commission and the Australian Competition and Consumer Commission will require telecommunications firms to report on wholesale and retail charges on data roaming, Communications Minister Amy Adams confirmed.
"They will collect, benchmark and report that publicly and they will be given the ability to intervene in the market in a series of ways, including setting price caps if they think it is necessary or requiring operators to offer local access services that don't require you to buy a local sim card."
Ms Adams said she knew quite technical-savvy people who had got back from holiday to bills that were higher than the cost of the vacations. "So this is a significant problem."
Increasingly crossing the Tasman was just like a provincial trip and more business was being done there.
The regulatory authorities would also be empowered to talk to other countries, such as the United States, Britain and some Pacific nations, about working with them on reciprocal agreements, Ms Adams said.
And while the concern was predominantly about data, the new regime would cover all roaming charges, including those for voice and text.
Meanwhile, Ms Gillard made it clear last night that there would be no movement on the issue of benefits that New Zealanders are able to receive in Australia, many of which were curbed in 2001.
She said the special relationship the two countries had was already reflected in Kiwis' right to work in Australia without restriction - a right given to no other country's people.
But both she and Mr Key indicated there will be some announcement about New Zealand's willingness to help Australia handle asylum-seekers who arrive by boat.
Mr Key said it was a regional problem that required a regional solution.
Roaming charges
In Australia
May, 2010:
* Vodafone: $29 per MB
* Telecom: $8 per MB
* 2degrees: $30 per MB
Now:
* Vodafone: Prepay $0.50 per MB
* Telecom: Prepay $1 per MB, $6-a-day flat fee
* 2degrees: Prepay $0.95 per MB
