The Health Department is seeking an urgent hearing in the Industrial Relations Commission to try to end industrial action by WA nurses.
It claims the nurses' move to close one in five beds in most public hospital wards is now affecting the care of patients.
Forty beds have already been closed at Sir Charles Gairdner Hospital.
At a mass meeting in West Perth yesterday, 1000 nurses and midwives voted to start closing beds in most hospital wards, including emergency departments.
Exemptions include beds used for cancer, paediatric, maternity and intensive care patients.
Nurses also voted to cancel one in five booked operations with the exception of emergency and category one elective surgery patients.
The Australian Nursing Federation said beds would be closed progressively as patients were discharged. Nurses were being told to strip beds, place a "bed closed" sign on them and refuse to accept new patients.
ANF secretary Mark Olson said nurses had been left with little choice after the Health Department refused to negotiate in the next wages agreement.
The union is seeking a 20 per cent increase over three years but the State Government has previously offered 9 per cent.
"There have been meetings but they've said they can't negotiate because we're in caretaker mode but that's not good enough," Mr Olson said. "They're also trying to say WA nurses are the fourth best paid of mainland States but that really means second last."
The ANF has been running full-page newspaper advertisements comparing the wages of nurses with police and teachers.
Director-general of health Kim Snowball said the action was irresponsible given it was more than four months before the nurses' agreement expired.
"I appeal to nurses not to follow through on this industrial action," he said. "The minute the action starts we'll be straight into the Industrial Relations Commission because we don't want to see patients put at risk.
"This is way early to be pulling the trigger on industrial action."
Mr Snowball conceded the department could not make an offer before the election but said it was determined to give nurses a fair hearing.
Any nurse who took unauthorised time off yesterday to attend the meeting would be docked pay.
Premier Colin Barnett said nurses had received a 4.5 per cent pay rise last September.
If re-elected, his government would negotiate with nurses to have a new agreement in place by the middle of the year.