The Afghan government says it is up to the judiciary to decide the fate of a man who could face death for converting to Christianity. Abdul Rahman, 41, is charged with rejecting Islam and could be executed under Sharia law unless he reconverts. But prosecutors, echoing earlier comments by the judge, said questions had been raised about whether he was mentally fit to stand trial. The US and three Nato allies have expressed concern over the case. Khaleeq Ahmed, deputy spokesman for Afghan President Hamid Karzai said: \"The judicial system is an independent system. \"This is a case that the family of the person brought against him. We are watching it closely and Afghanistan also respects human rights.\" Mr Rahman converted 16 years ago as an aid worker helping refugees in Pakistan. His estranged family denounced him during a custody dispute over his two children. His mental health was questioned by the judge earlier in the week and on Thursday prosecutor Sarinwal Zamari said there were doubts about whether he was fit to stand trial under Sharia law. The US made a subdued appeal for him to be allowed to practice his faith - but stressed it did not want to interfere. Germany, Italy and Canada, which all have troops in Afghanistan, also voiced concern over Mr Rahman\'s plight. The Italian foreign ministry said Mr Rahman\'s plight was incompatible with the defence of human rights and fundamental freedoms. (BBC)