MINNEAPOLIS (AP) — Allina Health says it's offering a new contract proposal to its union nurses who staff five hospitals in the Twin Cities area.

The company has asked the Minnesota Nurses Association to come back to the bargaining table. The union didn't immediately respond to the request Monday.

The nurses returned to work Sunday following a seven-day strike. The union and its 4,800 members began their walkout June 19 after failing to negotiate a new three-year contract with Allina Health. The main sticking point is the rising cost of health insurance.

Allina Health says its new proposal extends the end date for the health insurance plan most used by its nurses to Dec. 31, 2019. After that, nurses would transition to health insurance options that are available to other Allina Health employees.