U.S. soldier Manning, 23, was arrested in 2010 on suspicion of passing restricted material to WikiLeaks. The leaked material contained footage of a Baghdad airstrike and a classified military video which shows the crew of an American Apache helicopter gunning down a group of men who they thought had a rocket launcher. The men, in fact, included Reuters staff with a TV camera.

Today, British veterans of the wars in Iraq and Afghanistan (veteransforpeace.org.uk) will call for his release, saying that "exposing war crimes is not a crime."

Among the protesters will be Michael Lyons, a former Navy medic who was released from Colchester Military Prison in November. He served a seven month sentence for refusing to carry out rifle training in preparation for deployment to Afghanistan. Lyons had applied for Conscientious Objector status after reading the  "Afghan War Logs" released by WikiLeaks.

Lyons said:  "I am grateful to WikiLeaks for providing the information that enabled me to make an informed decision of conscience. I am outraged by the continued imprisonment of Bradley Manning, exposing war crimes is not a crime".

Bradley Manning is accused of leaking the  "Afghan War Logs" to WikiLeaks and has been held in U.S. military custody for 18 months. He faces multiple charges which would lead to a lifetime of imprisonment if convicted. His pre-trial hearing on Friday 16 December.

Manning has said that he hoped the release of documents would lead to "debates, and reforms. If not … than we're doomed as a species. I will officially give up on the society we have if nothing happens."

Amnesty International is calling for an end to the "inhumane" treatment of the Manning. Get more info here: action.amnesty.org.uk