Ammar Qorabi, head of the National Organisation for Human Rights in Syria, said in a statement: "Mohammed Thabet Helli has been sentenced by the State High Security Court to 12 years in jail for belonging to the Muslim Brotherhood."

He recalled that sentences by this court are final, with no recourse to an appeal.

Syrian law provides for the death sentence for membership of the Brotherhood but since the mid-1990s those in death row have had their sentences commuted to long terms in prison.

Qorabi added that the same court had sentenced two others, each to three years in prison for belonging to an unnamed "secret organisation"

The human rights activist denounced the verdicts of a court set up under the state of emergency in force since 1963, adding that "the rights of Syrians to freedom of expression and opinion, and to membership of organisations ... are guaranteed by the constitution."

He criticised the "Syrian authorities who ignore the claims of Syrian society to cancel the law decreeing the state of emergency and to free all political prisoners."

In a statement to mark International Human Rights Day, Qorabi equally called on the authorities to "allow all Syrians to exercise their political rights" and "pass a modern law on (political) parties and the environment" and "amend the law governing publications."

He repeated the organisation's demand for the release of all political prisoners, the scrapping of the emergency courts and a general amnesty to enable exiles to return home.