The attorney for a Viennese Jew sentenced to jail for failing to mention other heirs to property confiscated by the Nazis has requested that the case be reheard.

Robert Amsterdam of the London-based law firm Amsterdam & Partners has written an open letter requesting "an extraordinary reopening of the case, concerning both the verdict and the penalty" against his client, the journalist Stephan Templ.

In 2005, 38 people - of whom Mr Templ was one - applied for the restitution of a former sanatorium in Vienna that the Nazis had confiscated from their ancestor, Lothar Fürth, a Jewish doctor.

In April 2013, the court found Mr Templ guilty of failing to mention another possible heir - his 84-year-old aunt, who was reportedly estranged from his mother. The court argued that the aunt might have left her part of the property to the state had she been included in the restitution request.

A Regional Criminal Court in Vienna sentenced Mr Templ to three years in jail for serious fraud, with the Austrian state as victim. Although an appeal to the Supreme Court in Vienna on 22 January this year was rejected, a regional court subsequently reduced the sentence to one year in jail with two years' probation on June 6. The start of Mr Templ's jail term was then postponed from last August to September 2015.

In his 22-page letter addressed to Austrian Procurator General Werner Pleischl, titled "Request for Extraordinary Reopening of the Case", Mr Amsterdam said the case against Mr Templ was fundamentally flawed.

"How the Republic can lay claim to property that is acknowledged to have once been stolen and has been then given back to the heirs of the rightful owners is a fundamental error in the entire logic of the prosecution of Mr Templ," he wrote.

Mr Amsterdam added that he had taken on Mr Templ's case pro bono, as it "cries out for justice. For a Jew to be indicted and jailed by an Austrian court in these circumstances represents a grotesque violation of historical memory."

Mr Templ said: "The Austrian authorities, the Finanzprokuratur, confirm that I did not cause any damage to the Republic of Austria. That makes the verdict against me null and void.

"In addition, the head of the Criminal Court of Vienna, Friedrich Forsthuber, publicly stated that I did not cause any damage and that the Republic should not enrich itself by a once 'Aryanised' property.

"If Austria is a legal state they have to dismiss the verdict."