A Jewish American accused of spying on the Cuban government could find out today whether he is to spend the next two decades behind bars.

Alan Gross claimed that he was on the Communist-run island to support the Cuban Jewish community by providing them with internet access, but the authorities there accused him of subversive activity.

He was arrested in Havana in December 2009 while working as a contractor for a US international development programme.

The 61 year old, charged last month with "acts against the independence and territorial integrity of the state," is in court today and could face a 20-year sentence if he is found guilty.

The case has divided the Jewish community, with most of Cuba’s 1,500 Jews denying Mr Gross’s story. But US Jewish groups have called on President Raul Castro to release Mr Gross on humanitarian grounds, primarily because both his mother and daughter have cancer.

A letter sent to Mr Castro from the Conference of Presidents of Major American Jewish Organisations said: "Mr Gross has long been an active and committed member of the Jewish community in the United States. He has lived his life following the Jewish teachings of tikkun olam [repairing the world].

“When Mr Gross was arrested he believed he was advancing his humanitarian work in Cuba."

The US State Department is also working on securing Mr Gross’s release. "He has been in prison for too long," said State department spokesman PJ Crowley.