A former British soldier currently on death row in the Democratic Republic of Congo (DRC) faces trial today for the murder of his cellmate and best friend.

Joshua French and ­Tjostolv Moland were sentenced to death in 2009 after being found guilty of espionage and murder, although both men maintained their innocence.

They were convicted for a second time for the same offences in June 2010 following a military retrial branded a "farce" by campaigners.

However, French, who was born in Norway and brought up in England, now faces a fresh murder charge after Moland was found dead in the cell they shared in August last year, despite an initial investigation finding he took his own life.

Legal charity Reprieve has called on the UK Government to intervene to prevent the trial or, at very least, have it transferred to a civilian court as it is set to be held in a military court, in violation of international law.

French's mother Kari Hilde said: "Joshua has already lost his best friend and nearly five years of his life. Now he's being falsely accused of murder.

"How much more will he have to endure before the British Government takes serious action?"

Reprieve said a post-mortem examination conducted jointly by Congolese Police and the Norwegian police agency Kripos confirmed Moland had committed suicide.

Moland's father has ­written to the Congolese authorities asking for the charges against French to be dropped but the request has not been answered.

Maya Foa, director of Reprieve's death penalty team, said: "These are sham charges and the Prime ­Minister needs to intervene without delay."

French and Moland were convicted of murdering Abedi Kasongo who was shot after being hired to drive the two former soldiers after their motorbike broke down in April 2009..

French and Moland denied responsibility. They claimed gunmen ambushed them in the middle of a rainforest.

The prosecution told the courts Moland wrote a letter confessing he was a spy and was responsible for killing Mr Kasongo. But the letter was never given to his defence team.