The doctor shortage is now so acute that locums from New Zealand are being flown from across the Tasman to work in country hospital emergency rooms - at times, just for a weekend's work.

Locum doctors have long filled gaps in short-staffed hospitals around Australia but medical recruiters are now going to new lengths to find medical professionals.

Doctors from New Zealand are flying here for short-term work and earning up to $7,000 over a weekend, which is almost three times the pay of a full-time doctor.

Medical recruiter Sam Hazledine says he places about 300 New Zealand doctors a year as locums in Australia.

"The weekend warrior phenomenon for doctors is where you get a doctor who does have a permanent job in New Zealand and just wants to head over to Australia and earn massive dollars, very quickly and then come back to their standard job," he said.

One of those Kiwi workers is Jason Pascoe, who has moved from the near freezing city of Invercargill on New Zealand's south island to take on a three-month locum job at Port Macquarie, on the New South Wales mid-north coast.

"Number one for a lot of people is the pay," he said.

"You are paid more and I guess part of the reason is you don't have job security, it's a short-term stint. Often they're last minute and so you are compensated for that."

Port Macquarie, like most regional hospitals across the country, cannot get enough doctors.

At the hospital a team of Kiwi locums help keep the emergency room in operation 24 hours a day, seven days a week.

Dr Pascoe says it is quite a popular thing for New Zealanders doctors to come over for short stints.

"I wanted to do more emergency department type work, and although that is available in New Zealand... Australia being a lot bigger and having more hospitals, there's more of it available."

Counting the cost

Health authorities in Victoria, Queensland and Western Australia say it is too difficult to quantify the cost of supplying locum doctors.

In South Australia $5 million was spent last year on locums, that is a 10 per cent rise on the previous year.

In New South Wales the Government spent $59 million in the last financial year for locum doctors outside cities, or more than $1 million a week.

Richard Murray, dean of medicine at James Cook University in Townsville, has been studying the workforce needs of regional and remote hospitals for 15 years.

"We are short of doctors and we've got an ageing population, but that's certainly not the only thing," he said.

The Federal Government has recently ramped up its funding for rural doctors, announcing $130 million in incentives to keep doctors in rural areas and payments of up to $120,000 for doctors to leave the city.

From July 1 more than 3,000 overseas trained doctors will have their restrictions on where they can practice reduced, if they work in rural and remote communities.

Adding to that, Professor Murray says a recent surge in doctor training has buoyed health authorities into thinking Australia will eventually grow its own workforce.

"We've gone from a low of around about 1,200 odd domestic medical graduates a year with a relatively small number of international students who come in and train to get a medical degree in Australia, to something like just over 3,000 domestic graduates, in less than the space of 10 years and that is an astonishing level of growth," he said.

But he says the incentives are not yet in place to attract doctors to where they are needed most.

"If we just shoehorn all those graduates into highly specialised junior doctor training posts etcetera, in fact this could be a net negative and they won't trickle out," he said.

"Once you build that training capacity into major metropolitan hospitals, it's hard to then extract that at some later point and send to the bush.

"You really do need to take the opportunity now to build those pathways into regional Australia."

Until then it will be doctors like Jason Pascoe who will make the trans-Tasman trip to fill the workforce gaps.

"Most hospitals, when they've got locums, they would rather they be full-time, permanent staff," he said.

"I can certainly understand that, but I'm here for however long they need me."