Key Points:

National would wipe up to $10,000 a year off student loans for doctors, and $3500 for nurses who agreed to work in hard-to-staff areas.

National is releasing its health policy in parts and today's was on workforce.

Labour released National's health policy last week saying it was leaked to them. National say a batch of policies were accidentally left in a public place.

Today National leader John Key confirmed the party would set up voluntary bonding of health professionals to address shortages.

"We expect to be able to offer eligible candidates write-offs of up to $10,000 a year.

"The amounts would be payable at the end of three years, with the option to continue in the scheme for an additional two years after that."

Mr Key said between 50-100 doctors and 200 nurses and midwives would qualify for the scheme per year. He said the annual debt write-off for nurses would be around $3500 based on average debt levels at graduation.

The scheme was costed at about $3 million in its first year increasing to $9m in the third year.

"We want more of our doctors, nurses and midwives staying in New Zealand and working in areas that are hard-to-staff. This programme will incentivise them to do so, and relieve some of the staffing pressure in those areas."

The first three years of annual write-offs would be made at the end of the full three years. Remaining write-offs would be annual.

The scheme would be flexible to allow for training and maternity leave; would be extended to other health professionals in time; would operate alongside graduate's compulsory minimum loan repayments and would be open to those who graduated since 2005.