MINNEAPOLIS (AP) - More negotiations are planned in an effort to resolve a nurses' strike at five Twin Cities-area hospitals that began over three weeks ago.

A federal mediator called both sides back to the bargaining table Tuesday for the first time since the walkout began Labor Day in a dispute over health insurance, workplace safety and staffing levels.

A statement issued by Allina Health says both sides agreed to adjourn late Tuesday night and to reconvene Wednesday morning to continue their discussions. The statement provided no details on whether the health system and the Minnesota Nurses Association had made any progress toward resolving the dispute.

The affected hospitals are Abbott Northwestern and the Phillips Eye Institute in Minneapolis, United in St. Paul, Unity in Fridley and Mercy in Coon Rapids.