The case will be heard by the Court of Cassation in Rome on March 25th, Ansa reported.
Kercher had been studying in Perugia when she was stabbed to death in 2007.
Knox and Sollecito - originally sentenced to 26 and 25 years in prison for the murder - were acquitted on appeal in 2011 after four years behind bars, but then found guilty again in a shock about-turn by a Florence court in January.
The Florence court said there was DNA proof that three people were at the murder scene: Knox, Sollecito and a third person, Ivory Coast-born drifter Rudy Guede, who is the only person still in prison for the crime.
Both Sollecito and Knox have argued the crime scene was contaminated and any DNA collected was therefore not viable. Preparing for the appeal at the Court of Cassation, Sollecito’s lawyer earlier this year unveiled a new defence strategy in which she cast doubt on Knox’s alibi.
Italy’s highest court could either uphold the Florence verdict or order a retrial.
If the verdict is upheld, officials are expected to begin a lengthy battle to extradite the 27-year-old Knox from the United States, where she returned on her release from prison in 2011.