The New Zealand Nurses Organisation has voted in favour of nationwide strikes over pay and staffing concerns.
Spokesperson Cee Payne said the only time nurses, midwives and healthcare care assistants mounted a national strike was nearly 30 years ago.
She says nurses have agreed to stop working on 5 July and 13 July if necessary.
Later today the union will be given a revised offer from health boards, and Payne says members are expected to vote on that in June.
A no vote will mean strike action.