The Irish Nurses Organisation has rejected proposals by the HSE to end the row over staffing levels at Cork University Maternity Hospital.
The facility was due to open this afternoon, but it remains unclear whether or not this will go ahead.
At a meeting late last night, a majority of nurses and midwives due to transfer to the hospital voted against the move.
The Labour Court has urged the INO to co-operate, claiming 375 midwives and nurses is sufficient to operate the new facility.