Amanda Knox, the American student accused of murdering her British roommate in Italy in 2007, said on Friday that "common sense" told her not to return to Italy for a retrial due to begin on September 30.
"It's not a possibility," Knox said in an interview on NBC television's "Today" show. It is the first time she has said she will not go back to Italy.
"I was imprisoned as an innocent person and I just can't relive that," she told "Today" show host Matt Lauer.
Knox, 26, spent four years in prison for the murder of Meredith Kercher, whose half-naked body was discovered with more than 40 wounds and a deep gash in the throat in the apartment the two shared while studying in Perugia in central Italy.
Following an appeal, Knox and her ex-boyfriend, Raffaele Sollecito, were acquitted in 2011 and she returned to her Seattle, Washington-area home. The Italian Supreme Court ordered a retrial in March due to inconsistencies in the appeal court's decision to release Knox and Sollecito.
"There are so many factors that are not allowing me to go back - financial ones, ones where I'm going to school, ones where I want the court to proceed without distraction," Knox said.
"I was imprisoned as an innocent person. It's common sense not to go back," she added.
Knox does not have to attend the retrial and can be represented by her lawyers.
She said she expected to win acquittal again at the new trial and insisted that not traveling to Florence to face her accusers should not be seen as an admission of guilt.
"I look at it as an admission of innocence, to be quite honest," she said in the interview.
Knox maintained her innocence in a memoir released earlier this year and painted herself as a naive young woman railroaded by a foreign justice system.
Italy's Supreme Court has said the appeals court judges overlooked evidence against the accused. The high court wants a re-examination of the theory that Kercher was killed during a group sex game.
At the moment, only one person is in jail for Kercher's murder: Ivory-Coast born Rudy Guede, who is serving a 16-year sentence.