The Medical Council is urging striking junior doctors and their employers, the district health boards, to find common ground and talk.
About three thousand junior doctors from the Resident Doctors Association (RDA) walked off the job for two days last week and a similar strike is planned next week in a dispute over hours, rosters and pay.
Both sides have agreed to mediation on Thursday, but there is no indication of any compromise yet.
The RDA says DHBs are trying to reverse deals that have been part of their collective agreement for 15 years.
However, DHBs say they understand the doctors' union is already balloting members for more strikes in February, which suggests the Resident Doctors Association has decided not to find a solution.
Now, the regulatory body for all doctors, the Medical Council, says it's worried that the doctors and DHBs both appear to have well-entrenched positions.
It says while the urgent needs of patients are protected during strike action, the needs of other, less urgent patients could also be affected.
The council's chairperson, Andrew Connolly, said to avoid that, both sides must find another way to make progress.
In a [www.mcnz.org.nz/assets/News-and-Publications/Letter-from-MCNZ-re-strike.pdf letter to the RDA and DHBs], Mr Connolly wrote:
"There is no doubt that safe staffing is a vital foundation of safe patient care. I doubt either party wishes to challenge that view. I would ask both parties to urgently develop a cooperative mechanism to make real progress on safe staffing, but in an environment that allows the union membership to avoid strike action.
"I appreciate there are related issues of significant disagreement such as how roster changes are approved and introduced, but I would suggest the fundamental issue of safe staffing should be prioritised.
"Continued industrial action will ultimately threaten aspects of public health and safety. Whilst I am confident life preserving services can be maintained over repetitive 48 hour stoppages, at least in the immediate future, this is not equivalent to eliminating risk of harm to patients whose health needs fall short of "life preserving" scenarios."
He said he was prepared to meet with both parties to discuss the issues further.