Raffaele Sollecito speaks to journalists in Rome today

Last month, Italian judges reinstated a guilty verdict against Knox and her former boyfriend Sollecito , after the pair were acquitted of Kercher's murder on appeal in 2011. They are now awaiting a judgement from Italy's highest court, the Court of Cassation, which could uphold or overturn the verdict.

Knox has long claimed that she was with Sollecito, making love and watching TV, on the night Kercher was killed.

But at the news conference today, the 30-year-old IT graduate said he could not be held responsible for the actions of his former girlfriend, saying: "I am not the guarantor of Amanda Knox, I am Raffaele Sollecito."

Sollecito's attorney Giulia Bongiorno was also keen to distance her client's actions from those of Knox, and claimed much of the evidence against Knox has also been unfairly used to convict Sollecito.

Last month's judgement that reinstated the guilty verdict against Sollecito and Knox rested in part on a text message sent by Knox, in which she claimed she was in Sollecito's house when cell phone records actually placed her in a street.

"We are drawing attention to the text," said Bongiorno. "It shows Amanda was out, but has been used to prove the guilt of both Knox and Sollecito. Why?"

"I have always believed in the innocence of Amanda. But I have to react to the accusations of the court and to the text message," said Sollecito.

"Either the court has made their umpteenth mistake or she lied to me. I was in love with her and we had some very happy moments, but ultimately Amanda was a stranger.

"There are anomalies in her version of events. Against me there is nothing."

Raffaele Sollecito questions Amanda Knox's alibi in explosive new development