(AP) - Politicians will be excluded from speaking at this year's Sept. 11 anniversary ceremony at ground zero, following a year in which families have expressed concern that political struggles are hindering progress on a 9/11 museum at the World Trade Center site.

The foundation that controls the 9/11 memorial told family members that this year the reading of victims' names by relatives will be "the exclusive focus of the program," according to a letter sent to families Wednesday and shared with The Associated Press.

It was the first indication that the reading of the names would continue to be part of the ceremony as the 11th anniversary approaches. Some family members had protested after New York City Mayor Michael Bloomberg, the foundation's chair, had said he wasn't sure if the names should be read individually now that they are on display at the memorial at ground zero.

Construction of the museum planned to accompany the memorial has slowed amid financial and political disagreements between the powerful forces that control the space. The foundation is responsible for the memorial and museum, while the Port Authority of New York and New Jersey - jointly controlled by the governors of both states - owns the site.

Disagreements over the site have intensified in recent weeks, with some family members accusing New York Gov. Andrew Cuomo and New Jersey Gov. Chris Christie of betraying the dead, and others accusing Bloomberg and the foundation of blocking progress and allowing costs to spiral out of control. Many family members have expressed concern that the site is sliding back into political dysfunction.

Joe Daniels, president of the memorial foundation, said in a statement Wednesday: "The National September 11 Memorial is focused on honoring the victims and their families in a way free of politics, and this ensures that continues."

This year, as in other years, the observance will be broken by six moments of silence, marking the moments in which each World Trade Center tower was hit and fell, and the times of the attacks on the Pentagon and on United Airlines Flight 93, which crashed near Shanksville, Pa. In previous years, elected officials had read poetry or literary excerpts during the ceremony.

Bloomberg has said he wants to keep the site out of "the political process," while Cuomo's office has said the museum shouldn't be politicized, and a Christie spokesman has said no one wants to politicize the site.