Negotiators for Allina Health and its Twin Cities hospital nurses, who broke off talks early this week, met again on Friday — but only to outline rules under which the nurses will return to work after a seven-day strike that starts Sunday.

While the strikers' jobs are protected under federal labor law, Allina officials will have some flexibility in calling nurses back to work, according to an Allina document released Friday that summarized the "return to work" process.

The strike could reduce the number of patients coming to Allina hospitals over the next week, which in turn could reduce the need for nurses the following week. "Nurses will be returned to work following the strike based on patient care needs as operations require," the statement read. "Not all staff who are scheduled to work will be returned if our census or patient care needs do not support it."

Barring a last-minute settlement, the strike will start at 7 a.m. Sunday at five Allina facilities: Abbott Northwestern Hospital and Phillips Eye Institute in Minneapolis, United Hospital in St. Paul, Mercy Hospital in Coon Rapids and Unity Hospital in Fridley.

As many as 4,800 nurses represented by the Minnesota Nurses Association may participate in the strike, protesting an Allina contract proposal that would phase our their union-backed health benefits and move them to the company's insurance plans. Allina officials have argued that the union plans are costly and outdated, while union officials have argued that the plans provide key protection for nurses who are at high risk of workplace-related injury and illness.

Per the return-to-work rules, Allina must notify nurses at least eight hours before their shifts start. Nurses who show up for previously scheduled shifts without being called won't be paid.