Amanda Knox has told British television’s ITV that she will not return to Italy to attend her retrial for the murder of Meredith Kercher.

However in an interview from Seattle for ITV’s Daybreak programme she said that she would be prepared to take a lie-detector test to prove her innocence.

Knox was originally convicted, along with her boyfriend Raffaele Sollecito, for the murder in 2007 of her flatmate Kercher in Perugia. Both were imprisoned waiting a retrial and were subsequently acquitted in 2011. But earlier this year Italy’s Court of Cassation overturned the lower court verdict on procedural grounds.

The retrial is scheduled for the end of September in Florence.

Knox indicated in the television interview that the reasons she will not be returning to Italy are both emotional and financial. She said that she is innocent, that she is trying to rebuild her life and that she cannot afford the cost of returning.

Knox’s book Waiting to be Heard, based on her prison experiences in Italy, is said to have earned her an advance fee of about €3 million, but she said in the interview with ITV that this had already gone to paying off the debts of her previous trials.

The Knox interview with ITV comes shortly after a similar one in the US with NBC’s morning television show Today.