(CNN) - Hillary Clinton’s campaign responded Sunday to charges from rival Barack Obama that the New York senator “flip-flopped” on the issue of torture during her presidential campaign, saying she held strong positions against its use by government officials.

When President Bush vetoed a bill Saturday that would have prohibited the CIA from using harsh interrogation techniques, Obama used the occasion to criticize his Democratic presidential opponent.

"We need a Commander in Chief who has never wavered on whether or not it is acceptable for America to torture, because it is never acceptable,” said Obama. “While I have consistently opposed torture, in the course of this primary campaign Hillary Clinton has flip-flopped from her past position of tolerating torture. …

“When I am president, the American people and the world will be able to trust that I will outlaw torture, because unlike Senator Clinton I have never made an exception for torture and I never will."

Obama was making a reference to Clinton’s decision late last year to rule out any use of these techniques in interrogations, after a meting with a group of retired generals who opposed their use. Earlier, Clinton had said they might be an option if authorities suspected their use might help prevent an imminent attack – a position that was also held by her husband, former President Bill Clinton.

The Clinton campaign responded with a statement that said her “strong position opposing torture” had led to her endorsement by Gen. Antonio Taguba, who wrote the official report on the military’s Abu Ghraib scandal.

The release also included an excerpt of a recent letter Senator Clinton sent to President Bush in which she said strong opposition to torture was essential.

“I believe, as do the military leaders I have consulted, that any sign of wavering on this issue by the Commander-in-Chief ‘will drop down the chain of command like a stone, and the rare exception will fast become the rule,’” she wrote.

–CNN Associate Political Editor Rebecca Sinderbrand