"We're taking and will continue to take whatever steps are necessary to hold accountable those who may have violated the code of military conduct and betrayed the trust placed in them by the American people," Rumsfeld said.
The defense secretary disputed critics in Congress who have said his department moved too slowly and asserted that correct military procedures were followed. He said it takes time to deal with the allegations.
Many of the allegations of abuse were contained in an internal Pentagon report completed in February.
Outraged by the reported humiliation and abuses of Iraqis by U.S. military personnel at Baghdad's Abu Ghurayb prison, U.S. senators have called for Rumsfeld to explain the situation in an open congressional hearing as soon as possible.