The union representing nurses at the University of Vermont Medical Center is shifting the battlefield in its contract dispute with the hospital.

The Vermont Federation for Nurses & Health Professionals says it will make an announcement Thursday outside the Williston offices of the New England Federal Credit Union.

John Dwyer, NEFCU’s president and CEO, is a member of UVM’s Board of Trustees. Kathleen “Scottie” Emery-Ginn, a retired IBM executive, is both a hospital trustee and a member of NEFCU’s Board of Directors.

The union and the hospital have been negotiating a new three-year contract since late March. The nurses, who waged a two-day walk out in July, are working without a contract and are demanding a 23 percent pay hike over three years and increased staffing. The union also wants a $15 minimum wage for all hospital employees.

The hospital has offered the nurses an average 13 percent raise, almost double the increase it offered when negotiations began. 

Earlier this week, the union released the results of a survey of nurses, their family members and friends that said some patients wait months for an appointment at UVM. 

Bargaining is scheduled to resume August 13. 

Thursday’s press conference in Williston will include Lt. Gov. David Zuckerman and Sen. Chris Pearson, the union said in a press release.