Frustrated overseas-trained nurses want the Minister of Health to review the new nursing registration rules, which include an English language test.
The New Zealand Nurses Organisation has also questioned the tougher rules, saying they will lead to an outflow of nurses, putting public health and safety at risk.
But the governing Nursing Council says the number of registered nurses has increased since the change.
According to council figures, there were 43,916 registered nurses in 2007, which increased to 44,571 last year.
Since January 1, all applicants, including nurses from English-speaking countries like Britain and the United States, have been required to take an English language test before they would be considered for registration.
Seven out of 10 overseas-trained nurses spoken to by the Herald said they were put off by the new rules, and planned to take their skills overseas if they could not be registered.
Elizabeth Ryan, a nurse from Britain with 16 years' experience, will pursue her nursing career in Perth next month because she did not want to pay $295 to sit the test.
"I can't believe the arrogance of these people, thinking they are in a better position to teach English to the English," said Mrs Ryan, who moved from Nottingham last year.
John Ramos, healthcare assistant at Middlemore Hospital, said he too would move to Australia if the council did not recognise his qualifications and nursing experience in the Philippines.
"I am a qualified nurse and came to New Zealand with a dream of being a nurse here. I can't just stay on as a healthcare assistant forever."
Agnes Granada, co-ordinator for the Migrant Action Trust, said she would be leading a petition to have the Minister of Health review the rules.
"They are prejudicial and unfair, and if nothing is done, it will just be New Zealand's loss and Australia's gain when all the nurses leave."
Cora Upward, a former Auckland District Health Board nurse who has moved to Melbourne, said New Zealand had to compete with more than just easier registration rules to keep nurses.
Besides getting an allowance of about $17,000 to relocate, Ms Upward said she was also being paid a third more than her New Zealand counterparts.
A spokesman for Minister of Health Tony Ryall said the minister would not comment as "this was an operational matter for the Nursing Council" and "not a political one".
Carolyn Reed, the council's acting chief executive, said: "We need to be assured that the public of New Zealand will receive safe and effective care from nurses who can communicate effectively with a wide range of patients in a variety of settings."
The requirement of IELTS 7 for registration is similar to Britain, Ireland and even some states in Australia.
Ms Reed said that contrary to the public outcry that the new regulations were "discriminatory", they were introduced to reduce discrimination and to address concerns about nurses who might have studied English but not practised nursing using the English language.
She also denied that nursing degrees shorter than four years were rejected, saying it was council policy to access each applicant individually.