BOSTON — A strike is still planned for nurses at Tufts Medical Center after a mediation session between the union that represents them and the Boston hospital was unsuccessful.

Representatives from Tufts and the Massachusetts Nurses Association, which represents 1,200 nurses at the hospital, say both parties spent around 10 minutes together in the meeting before a federal mediator ended the discussion Friday.

The union has said the strike will begin the morning of July 12 and run until July 13. But hospital officials have said they plan to lock out striking nurses for four additional days while employing temporary workers.

Contract negotiations have gone on since April 2016. Concerns have been raised by union officials over “patient safety, lack of resources and lagging compensation.”

Both sides are set to meet Tuesday.