Washington ? A $38 million pledge to the Smithsonian Institution has been withdrawn after critics complained the exhibit it was to have financed would damage the institution’s integrity.

The withdrawal announcement Monday came less than three weeks after 170 activists and scholars complained that Smithsonian Secretary Lawrence Small, the institution’s chief executive, has commercialized the museums.

The Catherine B. Reynolds Foundation pledged the money in May, earmarked for a “Spirit of America” exhibition to honor as many as 100 prominent Americans. It had been scheduled to open in 2004.

The now-scrapped 10,000-square-foot exhibit was to highlight Americans that included ice skater Dorothy Hamill, basketball legend Michael Jordan and civil rights leader Martin Luther King Jr. When the donation was announced, Small called it “an extraordinary gift.”

The Smithsonian’s long-held policy dictates that it and not sponsors control the timing, content and intent of exhibitions.

In a statement, Marc Pachter, acting director of the history museum, said the “Spirit of America” project “was being developed in strict accordance with Smithsonian standards.”

An initial payment of $1.5 million for planning the exhibit is expected to be kept by the museum, said Melinda Mschado, its chief press officer.

The Washington Post quoted a letter from Catherine Reynolds as saying criticism of the exhibit’s focus on individuals rather than groups by Smithsonian staff was the main reason she changed her mind about giving the money.

“Apparently, the basic philosophy for the exhibit ‘the power of the individual to make a difference’ is the antithesis of that espoused by many within the Smithsonian bureaucracy, which is ‘only movements and institutions make a difference, not individuals,”‘ she wrote.

“After much contemplation, I see no way to reconcile these diametrically opposed philosophical viewpoints.”

No statement was expected from Secretary Small, said David Umansky, the Smithsonian’s chief press officer.

The Smithsonian was established in 1846 with a bequest by Briton James Smithson. It is an independent trust, comprising 16 museums and galleries and the National Zoo in Washington and research facilities in the United States and abroad.