Italy's top court on Tuesday (March 26th) overturned the 2011 acquittal of American student Amanda Knox and former boyfriend Raffaele Sollecito for the murder of Briton Meredith Kercher, and ordered a retrial.

The decision by the Court of Cassation adds a further twist to a long-running case whose initial handling was sharply criticised by independent forensic experts.

Prosecutors accused Knox and Sollecito of assaulting and killing Kercher in 2007 and they were initially found guilty and sentenced to 26 and 25 years in prison respectively after a trial that grabbed headlines all over the world.

In 2011, their convictions were overturned and they were released after serving four years in prison.

But the prosecution in the appeals case appealed Knox's acquittal.

Knox was convicted of murdering Kercher, her British roommate, in a grisly, sex-fuelled crime in the Italian hill town of Perugia.

She was cleared on appeal in October 2011 and returned from Italy to her Seattle-area home, where she has kept a low profile.

Kercher's half-naked body, with more than 40 wounds and a deep gash in the throat, was found in the apartment she shared with Knox in Perugia where both were studying.

The crime and the trial drew worldwide attention and criticism in the United States of the Italian legal system.

Knox is expected to talk publicly about the trial for the first time to ABC News in April, the network said in February.

The 25-year-old Knox will discuss the case with Diane Sawyer in an interview to be broadcast on April 30th - the same day her book "Waiting to Be Heard" is published.

Presented by Adam Justice