MINNEAPOLIS — The union representing about 4,800 nurses at five Allina hospitals in the Twin Cities area has notified the company it will begin a strike on Labor Day.

The Minnesota Nurses Association is required to give 10 days of notice to Allina so it can make arrangements to maintain patient care.

The walkout is to begin at 7 a.m. Sept. 5. It’s the second by Allina nurses since talks began in February over a new three-year contract.

The nurses say the strike will be open-ended, meaning it will continue until a deal is reached. Allina wants to transition its nurses to the same health insurance plan as its other employees to save $10 million a year. The nurses want to keep their current health plans with lower deductibles.