The Delaware Art Museum is planning to sell as many as four unnamed paintings to cover $20 million in old construction debt and replenish its endowment funds, the museum said Wednesday.

"After detailed analysis, heavy scrutiny, and the exhaustion of every reasonable alternative to relieve our bond debt, the trustees had two agonizing choices in front of them - to either sell works of art or to close our doors," museum chief executive Mike Miller said in a statement. "While today's decision is certainly hard to bear, the closure of this 100-year-old museum would be, by comparison, unbearable."

The Association of Art Museum Directors, the field's professional organization, holds that museums should not sell any objects in their care unless proceeds are used to enhance the institution's collection. After the announcement that the museum's board of trustees unanimously voted to sell off art, the group issued a statement deploring the action.

Timothy Rub, director of the Philadelphia Museum of Art and current president of the association, said the group had been working with the Delaware Art Museum to find other solutions to its funding problems. The museum completed a $32 million expansion and building project in 2005 and has been struggling with debt ever since.

Rub said that despite those struggles, he believed "there are other options that could have been further explored" to raise funds and avoid sales.

The museum did not identify which four works might bring $30 million, but did say no gifts or bequests would be sold. That would preclude sale of Raphaelle Peale's portrait of Absalom Jones (1810) and Edward Hopper's Summertime (1943). Both were gifts.