The senior doctor's union is criticising Health New Zealand's decision to call in the Employment Relations Authority to sort out pay talks.

Around 6000 doctors and dentists are walking off the job nationwide tomorrow and Wednesday.

The ERA's been requested to fix the terms and conditions of a collective agreement - in a move unprecedented for the public sector.

Association of Salaried Medical Specialists Executive Director Sarah Dalton says they've done some work with the ERA in the past.

"We were not happy with the way the ERA authority members applied themselves to the task, and we didn't find them to take an independent view."

LISTEN ABOVE